Systems and methods for turning pages in a three-dimensional electronic document

The present invention relates to systems and methods in three-dimensional electronic documents.

Magazines, journals such as trade journals and scientific journals, textbooks, photo albums, newspapers, etc. are becoming increasingly available in electronic form. However, many readers are reluctant to read these documents in electronic form. This is because electronic documents lack the characteristics of paper documents that readers are accustomed to.

A technique for reproducing the characteristics of a paper document in an electronic document is highly desired.

Virtual book display systems, such as e-book systems, PCs, PDAs, etc., display virtual books in a two-dimensional ("2D") or three-dimensional ("3D") manner. As used herein, "three-dimensional" refers to the realization of a three-dimensional appearance of an object on a two-dimensional display, as used throughout this disclosure.

Since page turning is a dynamic animation that starts and ends in a stationary open or closed book, how the static position of the book is displayed is a book during the page turning animation. It affects to a large extent how should be displayed, and vice versa.

<nplcit num="1"><text>Yi-Chun Chu, "How to Turn the Page", Proceedings of JCDL, 2003, p.186 ~ 188</text></nplcit>

<p> In a virtual book displayed in 3D, it is desired to incorporate a function that reproduces the page turning operation of an actual physical book.</p>

<p> The method according to the present invention is a method of rotating a part of an electronically displayed three-dimensional object, which includes a step of animating the rotation of a rotating portion of the three-dimensional object, and the animation includes the step of animating the rotation of the rotating portion of the rotating portion. A step of deforming the rotating portion by curling at least a portion around the virtual geometry shape is included, the curling step mapping a point above the rotating portion to a point above the virtual geometry shape. Including steps<u style="single">The virtual geometry shape is a cone, and the position of the apex of the cone, which is the virtual geometry shape, and the size of the apex angle of the cone are changed for each continuous frame in the animation.</u>One<u style="single">With the law</u>can do.</p><p> According to the present invention<u style="single">Those who</u>Law<u style="single">In</u>Step of receiving user input indicating the position on the 3D object<u style="single">Further</u>Including, the animation can be in different ways depending on the position indicated by the user.</p><p> The system according to the present invention is a controller that rotates a part of an electronically displayed three-dimensional object, the controller animates the rotation of a rotating portion of the three-dimensional object, and the animation is the rotating portion. The curling step maps a point above the rotating portion to a point above the virtual geometry shape, including deforming the rotating portion by curling at least a portion of the around the virtual geometry shape. Including doing<u style="single">The virtual geometry shape is a cone, and the position of the apex of the cone, which is the virtual geometry shape, and the size of the apex angle of the cone are changed for each continuous frame in the animation.</u>It can be a controller.</p>

An exemplary embodiment is described in detail with reference to the drawings below. In these drawings, similar elements are indicated by similar reference numerals.

The page turning feature of 3D virtual books has some drawbacks. As shown in Figure 1, a virtual environment 100 containing a 3D virtual book such as WebBooks® has a closed virtual book 110 or an open virtual book 120 in front 122, 124 with a virtual camera. When viewed, it looks like a reasonably real thing. In WebBooks®, the closed virtual book 110 models the top and part of the bottom of the book, and the open virtual book 120 models the tops 122, 124 of the book.

FIG. 2 shows the cut surface of a closed WebBooks® along the AA line of FIG. 1 as a rectangular box ABCD. FIG. 3 shows the open WebBooks® cut planes along the BB line of FIG. 1 as line ASs (including line segments AB, BC, CD, etc.), respectively. On the book cut surface, the book is cut in half on the front and back of the book, eg, in the direction perpendicular to the cover. As shown in Figure 3, the open virtual book 120 models the tops 122, 124 rather than the back of the book. In a virtual environment displaying an open virtual book, the back or bottom, such as front and back covers, may not be visible to the virtual camera. The transition between the closed book 110 and the open book 120 requires a change between the description of the closed book in FIG. 2 and the description of the open book in FIG.

FIG. 4 is a model diagram of a rotating page block 126 representing a rotating WebBooks® page. As the rotating page block 126 rotates in the direction of arrow 130, point J moves in the direction of arrow 140 until the rotating page block rotates 90 degrees from its initial starting position. Point J then moves in the opposite direction of arrow 140 until the rotating page block 126 rotates 180 degrees from its initial starting position.

WebBooks® also includes a page roughing technique (not shown) that simulates flipping multiple WebBooks® page sets at once. The page to be turned is represented by a plurality of rotated page blocks. However, while the page roughing technique provides the ability to quickly explore the page set for information of interest, the roughing technique requires that the composition of all rotating pages be displayed. To that end, WebBooks® preloads and stores the entire page structure in main memory. Preloading the entire page structure and storing it in main memory would result in a large system, severely limiting feasibility and limiting the number of pages allowed in a virtual book. Moreover, it is difficult to determine the number of page turns during page roughing.

Other 3D virtual books also attempt to model the page turning of a real physical book. FIG. 5 shows a virtual environment 200 containing a 3D virtual book in open position 220 with pages 222 and 224 on the left and right. FIG. 6 shows the cut plane of a 3D ebook at closed book position 210 as a rectangle ABCD. The virtual book also has a static baseline 228 located along line AB and at the bottom of the book at closed position 210. The rest plane is used as a rest reference line to help determine the relative motion of the pages of the virtual book during page rotation. The terms "front" and "back" refer to the side of the cut surface on which the front cover and back cover are placed, respectively. The reader may look at the front from an upper position on the front (ie, a plane perpendicular to the front).

FIG. 7 shows the cut plane of the 3D book at open position 220 along the CC line in FIG. As shown in FIG. 7, the open virtual book is modeled as at least left page block 222 and right page block 224, respectively represented by the rectangular polygons ABCD and BEFG, respectively. The static baseline 228, which corresponds to line AE, is used as a static reference line to help determine the relative motion of the pages of the virtual book during page rotation.

FIG. 8 is a model diagram of a rotating page block 226 representing a page of a virtual workbook whose pages are turned. During the page rotation animation, the bottoms of the left page block 222 and the right page block 224, which correspond to the lines AB and BE, respectively, remain stationary on the baseline 228, and the rotating page block 226 is the connection point. Rotate around J and H in the direction of arrow 230.

Modeling a 3D virtual book as a rectangle located relative to the bottom baseline 228 has some drawbacks. First, dropping the rotated page block 226 at the end of the animation leads to visual discontinuity. Second, when the virtual book is turned from one page to the next, the positions of the tops of the left page block 222 and the right page block 224 change dynamically. This means that the distance between the still camera and the top page of the virtual book is not constant, which means which two pages are displayed on the top page of the opened book. It will look different in size depending on it. Third, when the page is turned, the page remains flat.

The following detailed discussion relates to a particular application, namely a three-dimensional electronic book, and exemplary embodiments of the pagination system and method of the present invention can be used with it. However, this is for ease of understanding and familiarity, and the systems and methods of the exemplary embodiments should not be construed as limiting the types of applications available.

The pagination method and system includes three simultaneous processes: 1) rotation process, 2) translation process, and 3) transformation process. The rotation process takes a page or group of pages, called a rotation page block, around a rotation axis, such as the stitches of a virtual book, from one side of the book to the other side of the book. Gradually rotate along. When a page rotates around a rotation axis (eg, a seam) from one side of the workbook to the other side of the workbook, the page turning path includes trajectories at different positions on the page. The axis of rotation need not be fixed and can move relative to the rest of the book, as described above with reference to FIG. During the rotation process, some of the page blocks attached to the book binding, such as the left side of the rotating page block (when the page block is rotated from the right side of the book to the left side of the book), are stationary by the reader. Seen, the rest of the page block is moving. In the example shown in FIGS. 14-16, the cross section of the rotating page block, the parallelogram JKGC, looks solid and unrealistic when viewed from the cut plane perpendicular to the binding of the book. The transformation process, in an exemplary embodiment of the invention, produces a more realistic model of the rotating page block, i.e. the parallelogram JKGC, by more realistically transforming the rotating page block during page turning. ..

In the transformation process of the exemplary embodiment, the top and bottom surfaces of the rotating page block are curled around a virtual geometry shape, such as a cone. Curling is the process by which points in a rotating page block are mapped to corresponding points on a geometric object. The geometry shape has the same dimensions for each surface. Geometric shapes when pages move from one side of the workbook to the other side of the workbook to create different curved shapes at different frames, i.e. at different points along the page turning path. Sizes can vary. When the rotation process, translation process and deformation process are done simultaneously, the cross section of the rotating page block, i.e. the curved object JKGC shown in FIG. 21, is flexibly viewed by the reader.

FIG. 9 illustrates an exemplary embodiment of the 3D eBook 300 in closed position 310. FIG. 10 depicts a cut plane of an exemplary embodiment of a 3D ebook along the DD line of FIG. Since the length of the virtual book 300 is the length of each individual page, for example the distance between the top edge of the page and the bottom edge of the page, the length of the virtual book 300 was kept constant through the page turning animation. Is done.

As depicted in FIG. 10, the closed book 310 is depicted as a parallelogram ABCD. The terms "front" and "back" refer to the side of the cut surface where the front and back covers are located, respectively. The reader may look at the "front" side from a position above the front side. The width of the book, eg the lengths of lines AB and DC, can be determined by the width of the individual pages or by the width of the front or back cover. The thickness of the book, eg, the shortest distance between line DA and line CB, is determined by the thickness of the cumulative number of pages in the book, as well as the thickness of the front and back covers. The tilt angles ABC and ADC can be constant constants. The virtual book 300 may also have a top plane of the closed book 310 that corresponds to the line DC, eg, a static baseline 320 located in front, which is relative to the pages of the virtual book 300 during page turning. It is used as a static reference line to help determine movement.

FIG. 11 illustrates an exemplary embodiment of the 3D e-book 300 of FIG. 9 in the open position 330, the 3D e-book 300 in a perspective view showing the thickness of the left 332 and right 334 of the book 300. Is shown. The thickness of the left 332 and the right 334 of the book 300 represents the number of pages of the left and right 332 and 334 of the opened book 330, respectively. FIG. 12 depicts a cut plane along the EE line of FIG. 11 of an exemplary embodiment of the 3D ebook 300 at open position 330. In FIG. 12, the static baseline 320 corresponds to the line EE in FIG. 11 and the front of the page being viewed.

As depicted in FIG. 12, the stationary state of the exemplary embodiment of the 3D ebook 300 at the open position 330 of FIG. 11 is modeled as including at least two page blocks. Specifically, the page block 332 on the left is represented by the parallelogram ABCD, and the page block 334 on the right is represented by another parallelogram EFGC. A parallelogram is drawn, but the page block does not have to be a parallelogram. In this and other figures, more relaxed shapes are also acceptable. The page block 332 on the left side and the page block 334 on the right side are connected at a point C. Point C corresponds to the binding of the book. Similar to the virtual book 300 at closed position 310 shown in FIG. 9, the width of the left page block corresponding to line AB and the width of the right page block corresponding to line EF depend on the width of the individual pages. Can be decided. Also, similar to the virtual book 300 at the closed position 310 shown in FIG. 9, the width of the left page block, such as the distance between the lines DC and AB, and the width of the right page block, such as the line CG and The distance between the lines EF can be determined by the width of the individual pages and the cumulative number of pages in each of the books. The static baseline 320 of the virtual book 300 can be located in the top plane corresponding to the top of the book when viewed by the reader, and can correspond to the line DCG in open position 330. The static baseline 320 can be used as a static reference line during page turning to help determine the relative motion of the pages of the virtual book 300. The terms "front" and "back" refer to the side of the cut surface that the reader sees. For example, in the embodiment of FIG. 12, when the book is viewed from the "front" side, the reader sees the open page of the book. On the other hand, the "back" side is hidden from the reader's line of sight.

The dimensions mentioned above are essential properties of the book calculated and / or determined by various methods and systems known to those of skill in the art. For example, the length, width, and thickness of individual pages in a closed virtual book can be pre-determined, so the thickness of a closed virtual work can also be pre-determined to the total number of pages in a closed virtual book. Can be equal to multiplying the thickness of individual pages. Along with other parts of the book that may have different thicknesses than the individual pages, such as pages, the values in the thickness calculation may be added to account for coverage. In addition, since the number of pages in the left and right page blocks during the stationary state of FIG. 12 can be predetermined, the coordinates or points of the left and right page blocks with respect to the static baseline are also predetermined. Can be done. In addition, the location of the virtual book in the virtual environment is also predetermined. Many dimensions and coordinates are pre-determined, so once the book is selected for viewing by the reader, the book's geometry and static baseline position, such as the book's point coordinates in FIGS. 10 and 12, are , Preferably determined in advance. Therefore, the reader only has to choose between the virtual book to view and the number of pages in the virtual book to move forward or backward.

The following detailed description describes an embodiment of a series of page positions when the pages of the 3D electronic book 300 of FIG. 11 (or FIG. 12) are rotated. This exemplary embodiment depicts turning the pages of a virtual book forward or counterclockwise, but the pages of the virtual book also depend on the reverse or clockwise direction, or the position of the bindings in the book. Please understand that you can turn in other directions. It should also be understood that one or more pages of a book can be turned at the same time.

The number of pages to be turned is determined before turning the pages of the book forward (eg, counterclockwise). The page turning system determines the position of the right page block 334 to be turned to the left of the virtual book 330 opened from the right side of the book, representing the number of pages to be turned.

Figure 13 depicts the start of a page-turning animation for virtual book 330, where the page is in the initial page-turning position. First, the right page block 334 is split into a first part that represents the number of pages to be rotated and a second part that represents the pages left in the right page block after the first part is removed. .. The first part is the rotating page block 338 represented by the parallelogram JKGC. The thickness of the rotated page block 338, eg, the distance between the line JK and the line CG, can be determined by multiplying the number of pages to be rotated by the thickness of the individual pages. In addition, the second part, represented by the parallelogram EFIH, the new right page block 336 depicts the difference between the previous right page block 334 and the rotating page block 338. The second part is not rotated in this animation. Finally, the top surface of the left page block 332 corresponding to the line DC and the top surface of the rotating page block 338 corresponding to the line CG can be on the same line as the static base line 320.

Figures 14-17 depict an exemplary state of 180-degree counterclockwise rotation of the rotating page block 338, where the rotating page block is 45 degrees counterclockwise with respect to the initial start position of FIG. , 90 degrees, 135 degrees, and 180 degrees. During the rotation of the rotating page block 338, the top surface of the left page block 332 corresponding to the line DC and the top surface of the rotating page block 338 corresponding to the line CG do not line up with the static baseline 320. The following discussion describes in more detail the movements of the left page block 332, the right page block 336, and the rotating page block 338.

As depicted in FIGS. 14-17, the rotating page block 338 rotates around points J, H in the direction of arrow 340. At the same time, points J and H move toward the static baseline 320, upwards toward the position where point C was initially located in the animation, that is, along the direction of line JC in FIG. start. However, through the animation, the left page block 332 and the rotated page block 338 remain connected at point C, resulting in a downward translation 350 of the left page block 332 away from the rest baseline 320. Similarly, upon movement of the left page block 332, the right page block 336 and the rotated page block 338 remain connected at points J, H, and as a result, the right page block 336 translates upward toward the stationary baseline 320. Make a move 360.

As the page turning animation progresses, the tilt angle CJK of the rotating page block 338 gradually changes from the obtuse angle in FIG. 13 to the acute angle in FIG. However, the thickness of the rotating page block 338, i.e. the distance between the lines CJ and GK, remains constant.

As shown in FIG. 17, after the rotating page block 338 has rotated 180 degrees counterclockwise from the initial page turning position, the side of the left page block 332 corresponding to lines BC and AD is the rotating page block. It may be on the same side as the side corresponding to the 338 lines CJ and GK, respectively. In addition, the top surface corresponding to the line KJ of the rotating page block 338 and the top surface corresponding to the line JI of the right page block 336 may be on the same line as the static base line 320.

FIG. 18 depicts modeling an exemplary embodiment of the 3D eBook 300 in the open position at the end of the page turning animation. As shown in FIG. 18, a new left page block 370 is generated as a result of merging the rotated page block 338 of FIG. 17 with the left page block 332. From this, the top surface corresponding to the line KJ of the new right page block 370 and the top surface corresponding to the line JI of the right page block 336 are on the same line as the static base line 320.

The embodiments disclosed in FIGS. 14-16 show a robust rotating page block 338. However, as mentioned above, turning pages using the techniques disclosed in FIGS. 14-16 produces a somewhat unrealistic page turning effect. This is because the top and bottom surfaces of the rotating page block seen by the reader remain flat during page turning. The flat surface of the rotating page block 338 does not deform during page turning, so the page turning block 338 looks rather solid and looks like a piece of paper so that it can be seen when the actual physical book is turned. can not see.

More realistic by generating a set of page shapes in the pre-processing stage corresponding to different points along the page-turning path and applying the pre-processed page shape to the individual rotated pages, as described above. It is possible to generate a typical page turning effect. For example, if the rotated page block 338 is rotated in a real physical book, the rotated page block is such that the rotated page block 338 is from one side of the book like the right page block 334 to the left page block 332. As it is moved to the other side of the workbook, it will have different geometric shapes corresponding to different points along the path of travel. During page turning, a pre-computed set of shapes is applied to the page, and as the page rotates from one side of the book to the other side of the book, at a particular frame corresponding to a particular point of page turning. , Brings a specific page shape (ie, "rotating page shape"). A set of page shapes can be constructed by one of ordinary skill in the art. Alternatively, the set of page shapes can be calculated automatically using a mathematical simulation model.

Non-Patent Document 1 discloses a prototype page turning system that animates complete three-dimensional page turning. In Non-Patent Document 1, the dynamic page-turning motion is pre-calculated by a fabric-like simulation model using a mass-spring structure defined on a small quadrilateral grid. This simulation model, as seen by the reader, gives a resilient effect to page turning, which is generally impractical in modeling solid objects such as book pages. Furthermore, due to the repeatability of this simulation model, it takes minutes to hours to calculate a single page turn in the realization of the prototype. Another inconvenience of the method disclosed in Non-Patent Document 1 is that this method considers how the shape of the rotated page deforms or the page rotates as a function of the position on the page that the reader touches. It is a point that is not done. Another inconvenience of the method disclosed in Non-Patent Document 1 is that the page shape is calculated by the preprocessed shape of the page modeled using a quadrilateral grid of a certain resolution (eg 16x16 small pieces). Is. This means that the repeating polygon mesh is represented by the same quadrilateral grid. That is, a polygon mesh with 32x32 vertices cannot be used to represent a rotated page. This is a potential problem when you need to dynamically change the polygon mesh of a rotating page.

Page turning has certain properties and / or properties when viewed by the reader. These "page-turning" characteristics are preserved when pages are turned in a virtual book to keep the page-turning effect natural and appealing to the reader by providing a realistic page-turning effect. Should be. The characteristics of "page turning" that should be retained when the page is turned are 1) to maintain the smoothness of the curved page when the curved page is turned, and 2) to make a right angle at the corner of the page being turned. Maintaining, 3) minimizing page decompression or compression when flipping, and 4) gradually changing the page shape according to the position on the page where the page was first lifted during the page turning operation. including. By preserving these properties and applying the calculated page shape to a particular "moving" frame, it transforms a flat page into a curved shape, turning pages in a real physical book. It is possible to retain the look and feel of.

FIG. 19 depicts a page transformation with respect to the top surface of the rotating page block 338. The transformation of the rotating page block with respect to the bottom surface is performed in a similar manner. For example, the bottom surface, the cone, is placed along a line that is parallel to the y-axis and passes through the point J ́. Once the curved shapes of the top and bottom surfaces have been calculated, the other surfaces of the rotating page block (eg, left, right, front, and back of the rotating page block) can be easily constructed.

In FIG. 19, the top surface of the rotating page block 338 corresponds to the xy plane. The bottom of the top surface of the rotating page block 338 corresponding to the line C ́-G ́ is aligned with the x-axis. The left side of the top surface of the rotating page block 338 corresponding to the line SC ́ is aligned with the y-axis. The z-axis corresponds to the reader's line of sight on the top of the book. The three-dimensional cone 400 is placed in the xy plane. In this example, the side of the cone corresponding to the line VS can be placed on the y-axis. Therefore, in this example, the axis VC of the cone is not parallel to the xy plane. However, the axis is preferably in the yz plane. The side of the cone that corresponds to the line SV is the top of the rotating page block 338 that corresponds to the binding of the book as the rotating page block 338 is rotated from one side of the book to the other side of the book. It can be modeled to keep the left side of the face stationary or to move the seams as indicated by the points C ́ in FIGS. 20-22.

The reader rotates the rotating page block 338 by touching a point on the rotating page block 338, for example point G ́. "Touching" can be done by physically touching the display screen if touch screen technology is used, or by pointing and clicking, for example, using a mouse. After the reader touches G ́, both the top and bottom of the rotating page block 338 begin to deform. The top surface begins to deform by curling around the outer part of the cone 400. As mentioned above, the side of the cone 400 is located on the line corresponding to the line SC ́. The bottom surface is deformed by curling around the over side of the second cone 410 (see Figures 20 and 21), where the side of the cone 400 is located on the line corresponding to the line SC ́. To start. However, the side of the second cone is located at the point J ́. Curving around the outer edge of the cone 400 The curl of the top and bottom of the rotating page block 338 results in a curved page block. Cone angle θ and cone apex V_yThe value of is the same for each cone and can be varied over animation time t ́ to obtain different views or phases of rotated page blocks, i.e. different curved page blocks. Animation time t ́ is all required to rotate the rotating page block 338 from one side of the workbook corresponding to the right page block 336 to the other side of the workbook corresponding to the left page block 332. It corresponds to the time.

As mentioned above, the cone angle θ and the cone apex V_yThe value of, i.e. the position, can be the same for each cone. However, the rotation of the top surface of the rotating page block can be modeled using a geometry shape that is different from the geometry shape used for the rotation of the bottom surface of the rotating page block. From this, the top surface can be rotated using a cone, and the bottom surface can be rotated using a cylinder. Preferably, for each of the calculations, the first geometry is used to model the top surface and the second geometry is used to model the bottom surface. In the following, it is described that the rotating page block is rotated by using the first cone for the top surface and the second identical cone for the bottom surface.

In this example, the cone angle θ for both cones is equal to 90 degrees before the reader touches the point G ́ prior to rotating the page, for example to rotate the rotating page block 338. As such, there is no curl of the page around the cones 400, 410, or as can be understood instead, the curl of the page around the cones 400, 410 is flat. As the page turning progresses, the cone angles θ and cone vertices V of cones 400 and 410_yThe position of is gradually changing. Cone angle θ and cone apex V_yThe position corresponds to the position of the rotating page block 338 as the rotating page block 338 rotates from the right page block 336 to the left page block 332.

For example, when the rotating page block 338 rotates from the right page block 336 to the left page block 332, the cone angle θ is the minimum cone when half of the page deformation occurs gradually from 90 degrees at the start of the page turning animation. It decreases to the angle θ. A point equal to the minimum cone angle θ and / or 1/2 of the page deformation corresponds to half of the total animation time t ́. When the cone angle θ begins to change, the position of the cone apex V corresponding to the y-axis moves on the y-axis toward negative infinity in the direction of the arrow L. The top and bottom points of the rotating page block 338 change as the shape of the cone changes (eg, cone angle θ and cone apex position V)._y(As it changes), the rotating page block 338 maps the points on the top and bottom of the rotating page block 338 to the corresponding points on the virtual cones 400, 410 into each successive frame of the page turning animation. It is deformed as it is mapped to cones 400 and 410 of different shapes. From this, when the point P is mapped from one cone to the next, the page is from the xy plane around the outer part of the cone 400, with its lower right corner corresponding to G ́ first. Lifted and curled. Therefore, G ́ is deformed and rotated before the rest of the rotation page block 338.

When the rotating page block 338 reaches the midpoint of the deformation process, the cone angle θ gradually increases to 90 degrees, and the cone apex V_yTranslates in the direction opposite to the direction of arrow L. From this, in the deformation process, the cone angle θ initially decreases from 90 degrees to the minimum cone angle θ, and the cone apex V_yTranslates in the direction of the arrow L toward negative infinity along the y-axis. Then, as the deformation process approaches the midpoint, the cone angle θ and the cone apex position V_yAt the same time reaches the minimum value, from which the cone angle θ increases toward 90 degrees and the cone apex position V_yTranslates in the direction opposite to the direction of the arrow L and travels toward the origin C ́ (or J ́). Thus, in an exemplary embodiment, the second half of the deformation process can be a mirror image of the first half of the deformation process.

For example, at any given point at time t ́, a given point P (P) on the top surface of the rotating page block 338, as shown in FIG._x, P_y, 0) are mapped to 400 specific points on the cone. A specific point on the cone 400 to which the point P is mapped has a radius R<maths num="1"><img file="JP4746972B2_D0001.tif" /></maths>It can be calculated by drawing a circle represented by. Around V on the xy plane. Here, R corresponds to the length of the line VP. The intersection of the circle and the y-axis is the point S. Based on the cone geometry, when the rotating page block 338 is wrapped around the cone 400, the arc SP coincides with a circular cross section that is parallel to the bottom of the cone and intersects the point S. If the point P is mapped to the point T on the cross section of the cone, then the arc ST and arc SP have equal lengths (| ST | = | SP |). Assuming that the center of the cross section is C and the angle SCT is β, the following relational expression is derived.<maths num="2"><img file="JP4746972B2_D0002.tif" /></maths>Where r is the radius of the cross section (Note: the angle SAP should be converted to SVP) and also<maths num="3"><img file="JP4746972B2_D0003.tif" /></maths>Is.

Point T (T_x, T_y, T_z) Makes the point S around the line (x = 0, z = r) the point S ́ (S)_x ́, S_y ́, S_z Rotate β to ́), then line S ́ (y = s)_y, Z = 0) can be calculated by rotating by θ. The point T can be calculated as follows.<maths num="4"><img file="JP4746972B2_D0004.tif" /></maths>

Functions θ (t) and V_y(t) can be constructed empirically to ensure smooth animation. The combination of translation, rotation, and transformation of rotating page blocks is discussed in detail below.

Figures 20-23 depict exemplary states of translation, rotation, and deformation of the rotating page block 338 during the page-turning animation, where the rotating page block is the initial rotation position shown in FIG. It is rotated 180 degrees counterclockwise with respect to. The following discussion describes in more detail the movements of the left page block 332, the right page block 336, and the rotating page block 338.

As shown in FIG. 19, the geometric shape, such as the circular cone 400, is located in the xy plane. The side of the cone touches the xy plane at point C ́ along the y-axis. FIG. 20 shows a view of the cut surface through the left and right sides of the open book. As can be seen from FIG. 20, even if the bottom surface of the cone 400 is circular, the cut surface of the cone 400 is slightly elliptical. Because the view of the cone is not perpendicular to the axis of the cone. The sides of the cone, located along the y-axis and modeled to touch the y-axis at point C ́ in Figure 20, can be horizontal or z-axis along the x-axis corresponding to the static baseline 320. Does not move vertically along. In this regard, the cone 400 can remain stationary, such as the baseline 320. θ and V_yThe size of the cone, including, is variable depending on a particular point during the animation time t ́ (ie, a particular frame of page turning as the page rotates from one side of the workbook to the other side of the workbook). As such, the cone 400 shown in Figures 20-21 is not drawn to a particular scale. For example, the page-turning animation has not yet started in FIG. 20, so at this point the cone angle θ is equal to 90 degrees. On the other hand, the cone shown in FIG. 21 has a cone angle θ smaller than 90 degrees.

As mentioned above, a particular conical shape is generated for each frame of the page turning process. The shape of the cone is a factor such as where the reader first touches the rotating page block and the specific point of rotation of the rotating page block along the page-turning path (ie, the point between the animation times t ́). It depends on. For example, the embodiments discussed throughout this specification correspond to page turning from the lower right corner of the right page block, but the methods and systems disclosed herein are paged from other positions on the page. It can also be used to rotate. For example, the right page block can also be rotated from the top right corner of the page. In this case, the cone 400 shown in FIG. 19 is rotated 180 degrees with respect to the common boundary between the right and left page blocks. The process discussed here is then applied to generate and rotate the rotating page block, where the upper right corner of the rotating page block, eg, point N in Figure 19, is first lifted and the other rotating page blocks are lifted. Rotated prior to the point.

In the page turning animation, the rotating page block rotates from one side of the book binding, eg, right page block 336 to left page block 332, during the animation time t ́, as shown in Figure 20. It refers to the cumulative frame that the reader sees as it translates and transforms. Each frame is generated based on a rotation, translation, and transformation process and corresponds to a particular point in the path of movement of the rotating page block.

Figures 20-23 depict exemplary page turning in a 3D ebook using the techniques described above in connection with FIG. 19 to rotate, translate, and transform a rotating page block. .. Figures 20-23 depict cut planes of virtual books taken along the x-axis.

FIG. 20 depicts, for example, a cross section of the page of FIG. FIG. 20 shows a frame of the rotation animation just before the rotation page block 338 is rotated. Baseline 320 corresponds to the top surface of the left and right page blocks. Since the rotated page block has not been rotated yet, the cone angle θ is equal to 90 degrees. As described above, the user touches a point on the page block to start the page turning animation.

As depicted in FIG. 21, the rotating page block 338 rotates around points J ́, H ́ in the direction of arrow 340. As the rotating page block 338 rotates, points J ́ and H ́ move upwards toward the static baseline 320, toward the position where point C ́ was located at the start of the animation, for example in Figure 13. Move along the direction of line JC (Note: this is a translation process for rotating page blocks). However, throughout the animation, the left page block 332 and the rotating page block 338 remain connected to the point C ́, resulting in a downward translational motion 350 away from the stationary baseline 320 of the left page block 332. Similarly, at the same time as the left page block 332 moves, the right page block 336 and the rotating page block 338 remain connected at points J ́, H ́, and as a result, towards the static baseline 320 of the right page block 336. An upward translational motion 360 is brought about.

At the same time that the rotating page block 338 rotates around the points J ́, H ́, the top and bottom surfaces of the rotating page block 338 are mapped to the cone 400, and the cone tangent to the xy plane at the point C ́ along the y-axis. Curled around the sides of the. As described above with reference to FIG. 19, the rotating page block 338 deforms because the points of the rotating page block (eg, points G ́ and P) correspond to the points above the cone 400. The point above the cone 400 is at the animation time t ́ because the shape of the cone changes (or instead, as can be understood, a cone of a particular shape is generated for each frame of the page turning animation). Relatedly, the rotating page block 338 is deformed by curling its top and bottom surfaces around a cone. As mentioned above, once the page-turning animation begins and the page begins to deform by curling around the cone 400, the angle θ of the cone decreases from 90 degrees and the apex V of the cone moves in the direction of the arrow L. To do. The next page-turning animation frame is then calculated for the cone angle θ less than 90 degrees and the apex V of the cone located further down the y-axis.

As shown in FIG. 22, after the rotating page block 338 has rotated 180 degrees counterclockwise from the initial page turning position, the side of the left page block 332 corresponding to B ́-C ́ and A ́-D ́. The part is on the same line as the side part corresponding to the lines C ́-J ́ and G ́-K ́ of the rotating page block 338, respectively. In addition, the top surface of the rotating page block 338 corresponding to K ́-J ́ and the top surface of the right page block 336 corresponding to J ́-I ́ are on the same line as the baseline 320.

FIG. 23 depicts an exemplary state of a 3D electronic block at open position 330 at the end of the page turning animation. As shown in FIG. 23, a new left page block 370 is generated as a result of merging the rotated page block 338 with the left page block 332 of FIG. From this, the top surface of the new right page block 370 corresponding to K ́-J ́ and the top surface of the right page block 336 corresponding to J ́-I ́ are on the same line as the baseline 320.

Since the quiesce state of the closed virtual book 310 in FIG. 10 does not have a left or right page block, the quiesce state of the closed virtual book 310 is considered to be a special case of the quiesce state of the open virtual book 330 in FIG. Be done. In other words, in the closed virtual book 310, one of the right page block and the left page block is considered to be invisible. Thus, the transition between the closed book 310 and the open book 330 is the transition between the open book 330 in the stationary state of FIG. 20 and the open book 330 in the stationary state of FIG. 23 as described above. The same is true. Therefore, the rotation of the virtual book page from the closed position 310 in the initial / final quiesce state to / is not discussed in detail. This allows the reader to perform page turning operations (eg, rotate, translate, and transform) by starting with a stationary closed or open book in a virtual environment. In other words, the page-turning cycle starts with a book in a resting state, for example as shown in FIG. 20, and goes through an animation as depicted in FIGS. 21 and 22, which is shown in FIG. 23, for example. It returns the book to other resting states such as.

24 and 25 individually depict exemplary embodiments of the page frame during the page turning animation. FIG. 24 depicts a page that is rotated about 45 degrees and deformed corresponding to a cone angle θ smaller than 90 degrees. FIG. 25 depicts a page that is rotated slightly less than 90 degrees and the cone angle θ is further reduced. Further, in the exemplary embodiment shown in FIG. 25, the cone apex V is located further down the y-axis towards negative infinity when compared to the exemplary embodiment shown in FIG. ing.

FIG. 26 is a schematic flowchart of an exemplary embodiment of a method of representing page turning in a three-dimensional virtual document. As shown in FIG. 26, the process of this method begins at step S1000 and continues to step S1100, where the reader obtains the 3D document to be viewed. Then, in step S1200, the selected 3D document is displayed as a left page block connected to the right page block in a resting state based on the predetermined dimensions. Then, in step S1300, the number of pages to be turned either forward or backward is selected by the reader. The choice of page number can be direct or indirect. An example of direct selection is when the reader manually enters a number such as "10". An example of indirect selection is when the reader simply touches the currently displayed page and the system understands that only that page should be turned (Note: in step S1300, for example as an option. By providing the S1430 (not shown), in the case of direct selection, the system can determine where to curl the page first, for example following what was done in the last page turn, or in a random fashion. ). Processing then continues to step S1400.

In step S1400, the movement of the left page block, right page block, and rotated page block was formed by a static baseline and a geometric object with its sides placed on the y-axis, based on the number of pages selected. Animated with respect to the plane. Then, in step S1500, it is decided whether more pages should be turned. This decision may be based, for example, on whether all pages of the document have been turned over, or at least whether the pages have been opened for a given amount of time. If so, the process jumps back to step S1300. Otherwise, the processing of this method follows step S1600, where the processing of this method ends.

27A and 27 are schematic flowcharts of an exemplary method for animating the movement of left and right page blocks, and rotating page blocks, based on a selected number of pages and with respect to baseline and geometric objects. is there.

The process of this method begins at step S1400 and follows step S1405 where, for example, the right page block is split into a rotating page block and a new right page block. As discussed earlier, the rotated page block is the first part that represents the number of pages that should be rotated, and the new right page block is the second that represents the pages that remain in the right page block after the first part is removed. It is the second part. As mentioned earlier, the thickness of the rotated page block can be determined by multiplying the number of pages to be rotated by the thickness of the individual pages, and the thickness of the new right page block is the first right page. It can be the difference between the block and the rotating page block, and the top surface of the left page block and the top surface of the rotating page block can remain on the same line as the baseline. The process then continues to step S1415.

In step S1415, the animation time t ́ is set equal to the time required to rotate the rotating page block from one side of the workbook to the other side of the workbook, and the animation time t is set to zero. .. At the same time, the coordinates of the baseline, as well as the coordinates of a three-dimensional shape such as a geometric cone with a cone angle equal to 90 degrees and a cone apex at a particular position on the y-axis, are calculated.

Next, in step S1420, the translation and rotation of the left page block, the right page block, and the rotated page block are determined at animation time t, for example using the above equation.

In step S1425, the geometry cone is placed between the left and right page blocks, preferably with the sides of the cone located on the y-axis.

Then, for example, in step S1430 (not shown), the reader selects a page position to start page turning, and this selection is accepted by the system.

Then, in step S1435, the coordinates of the selected point on the rotating page block where page turning begins, eg, the position of point G ́ in FIG. 19, and the coordinates of its corresponding point on the cone are the specific cone angles. And determined based on the function of the geometry of the cone with respect to the position of the cone apex. At the same time, the coordinates of the other points on the cone to which the remaining points on the rotating page block are mapped are calculated based on the geometry of the cone.

Then, for example, in step S1445 (not shown), the translated / second connection points of the rotating page block, such as the points (s) J ́, H ́ in FIG. 20, are at the beginning of the page turning animation, for example. Based on the functions of the animation times t, points J ́, H ́, and points C ́ in FIG. 20, it is determined using, for example, the above equation.

Then, in step S1450, the rotating page block is transformed by mapping points on the rotating page block (eg, point P) to their corresponding points on the cone (eg, point T). At the same time, the rotating page block rotates around the stitches of the virtual book. Since points such as J ́, H ́, and P can be determined at animation time t, the positions of points J ́, H ́, and P, and the remaining points of the rotating page block are during animation time t ́. At a particular point in, it can be determined whether the rotating page block moves at a relatively constant speed or at a variable speed.

Note that, for example, in step S1455 (not shown), the right page block, for example, E ́F ́I ́H ́ in FIG. 21, is translated upward based on the movement of the points (singular or plural) J ́, H ́ of the rotating page block. .. The right page block, eg E ́F ́I ́H ́ in Figure 21, may remain connected to the rotating page block throughout the animation.

In step S1460, the left page block, eg A ́B ́C ́D ́ in FIG. 21, is translated downward based on the movement of the rotating page block, eg point C ́. The left page block, eg A ́B ́C ́D ́, may remain connected to the rotating page block throughout the animation.

Next, for example, in step S1465 (not shown), the left page block, the right page block, and the rotated page block are displayed.

Then, in step S1470, the time is measured and t is set equal to the elapsed time from the start of the page turning animation. In step S1475, it is determined whether the animation time t is less than the predetermined time amount t ́. As mentioned above, the predetermined amount of time t ́ corresponds to the time required for the rotating page block to rotate from the right page block to the left page block. If so, processing continues to step S1420. Otherwise, the process jumps to step S1480.

If the process jumps to step S1420, step S1420 calculates a new cone shape (or new cone) with a cone angle and cone apex position that is different from the previous cone angle and cone apex position. And S1420 to S1470 are repeated.

At step S1480, the left page block and the rotated page block are combined to form a new left page block. For example, as shown in FIGS. 22 and 23, a new left page block is generated as a result of merging the rotated page block with the first left page block. From this, the top surface of the new left page block and the top surface of the new right page block are on the same line as the static baseline. The process then follows step S1500, which corresponds to step S1500 in FIG.

FIG. 28 is a flowchart showing in more detail an outline of an embodiment of a method of determining the coordinates of points of a left page block, a right page block, and a rotating page block at an animation time t = 0. As shown in FIG. 28, the process of this method begins at step S1405 and continues to step S1406. In step S1406, the thickness of the rotated page block is determined based on the number of selected pages to be rotated and the predetermined thickness of the individual pages . Then, in step S1407, the thickness of the new right page block is determined based on the difference between the predetermined thickness of the first right page block and the thickness of the rotating page block. Next, in step S1408, the initial coordinates of the points of the left page block, the new right page block, and the rotated page block are determined. The process then continues to step S1409, where the process of this method returns to step S1415 of FIG.

FIG. 29 is a functional block diagram illustrating an outline of an exemplary embodiment of the document rotation control system 500. As shown in FIG. 29, this document rotation control system 500 includes an input / output interface 510, a controller 520, a memory 530, and a page block determination circuit, routine, or application 540, each of which is one. It is properly interconnected by the data bus 550 or higher. The input / output interface 510 is linked to the display device 600 by a link 610 and to one or more user input devices 700 by one or more links 710.

Each of the links 550, 610, and 710 can be any known or later developed connection system that can be used to connect each device to the document rotation control system 500. It should also be understood that the links 550, 610, and 710 do not have to be of the same type.

Memory 530 can be embodied using any suitable combination of variable volatile or non-volatile memory, or non-variable or fixed memory. Variable memory, whether volatile or non-volatile, is any one of static or dynamic RAM, floppy disks and disk drives, writable or rewritable optical and disk drives, hard drives, flash memory and the like. It can be embodied by using one or more. Similarly, non-variable or fixed memory can be by using any one or more such as ROM, PROM, EPROM, EEPROM, and optical ROM discs such as CD-ROMs or DVD-ROM discs and disc drives. , Embodied.

The user input device 700 includes one or more touchpads, touch screens, trackballs, for inputting data and / or control signals into the document rotation control system 500 to rotate pages of a three-dimensional electronic document. It can be a mouse, keyboard, stylus, or any known or later developed user input device 700.

In general, the display device 600 can be a virtual document and any device capable of displaying the movement of the left page block, the right page block, and the rotating page block according to the techniques described above.

The page block determination circuit, routine, or application 540 receives user input to determine the dimensions and coordinates of a closed or open virtual book. The page block determination circuit routine, or application 540, then determines the dimensions and point coordinates of the left page block, right page block, and rotating page block for the rotation, translation, and transformation processes at animation time t.

An exemplary embodiment of the document rotation control system 500 for turning pages of a three-dimensional electronic document according to FIG. 29 may operate as follows.

User input is output from the user input device (s) 700 via link 710 to the input / output interface 510 of the document rotation control system 500. This user input contains information about the virtual document to be viewed, the number of pages that should be rotated before or after, and what is touched by the reader on the document. For example, variables related to the changing cone shape (eg, maximum and minimum values for cone angle and cone vertex position) may be entered by the user or programmed into the page block determination circuit, routine, or application 540. .. The controller 520 inputs user input information into the page block determination circuit, routine, or application 540.

Controller 520 controls the page block determination circuit, routine, or application 540 to determine the thickness of the rotating page block based on the number of pages selected and the predetermined thickness of the individual pages, and the right page block. Is split into a rotating page block and a new right page block. The controller 520 then controls the page block determination circuit, routine, or application 540 to determine the position of the static baseline and geometry used in the rotation and deformation process. Controller 520 then controls the page block determination circuit, routine, or application 540 to produce left page blocks, right page blocks, and rotation page blocks at animation time t for rotation, translation, and transformation processes. Determine the point coordinates of all the specified points. Finally, the controller 520 controls the display device 600 to display an animation as the left page block, the right page block, and the rotating page block rotate, translate, and transform during the rotation process.

<figref num="1">It is a diagram depicting an embodiment of a virtual environment including a 3D ebook, some of which are shown in the open position and some of which are shown in the closed position.</figref><figref num="2">It is a cross-sectional view along the AA line of FIG. 1 of a three-dimensional electronic book in a closed position.</figref><figref num="3">It is sectional drawing of the 3D electronic book of FIG. 1 in an open position.</figref><figref num="4">It is sectional drawing of the page turning which illustrates the page turning of the 3D electronic book of FIG.</figref><figref num="5">It is a figure which draws the embodiment of the virtual environment including the 3D electronic book in an open position.</figref><figref num="6">It is sectional drawing of the 3D electronic book of FIG. 5 in a closed position.</figref><figref num="7">It is sectional drawing of the 3D electronic book of FIG. 5 in an open position.</figref><figref num="8">FIG. 5 is a cross-sectional view of an exemplary page turning of a rotating page block in the three-dimensional electronic book of FIG.</figref><figref num="9">It is a figure which draws the embodiment of the closed 3D electronic book.</figref><figref num="10">It is sectional drawing of the 3D electronic book of FIG. 9 in a closed position.</figref><figref num="11">It is a figure which draws an exemplary embodiment of a virtual environment including an open 3D electronic book.</figref><figref num="12">It is a stationary cross-sectional view of page turning of the three-dimensional electronic book of FIG.</figref><figref num="13">It is a figure which draws an exemplary page turning of the 3D electronic book of FIG. 11 including a rotating page block at the start of a page turning.</figref><figref num="14">It is a figure which draws an exemplary page turning of the 3D electronic book of FIG. 11 which rotates a rotating page block 45 degrees counterclockwise.</figref><figref num="15">It is a figure which draws an exemplary page turning of the 3D electronic book of FIG. 11 which rotates a rotating page block 90 degrees counterclockwise.</figref><figref num="16">It is a figure which draws an exemplary page turning of the 3D electronic book of FIG. 11 which rotates a rotating page block by 135 degrees counterclockwise.</figref><figref num="17">It is a figure which draws an exemplary page turning of the 3D electronic book of FIG. 11 which rotates a rotating page block 180 degrees counterclockwise.</figref><figref num="18">It is a figure which draws an exemplary page turning of the 3D electronic book of FIG. 11 at the end of rotation of a rotating page block.</figref><figref num="19">FIG. 6 depicts an exemplary embodiment of page turning, comprising transforming a rotating page block by mapping a point on the rotating page block to a point above a virtual geometry shape.</figref><figref num="20">It is a figure which draws an exemplary page turning of the 3D electronic book of FIG. 11 using the virtual geometry shape shown in FIG.</figref><figref num="21">FIG. 6 depicts an exemplary page turning of a 3D ebook of FIG. 11 in which a rotating page block is rotated counterclockwise using the virtual geometry shape shown in FIG.</figref><figref num="22">It is a figure which draws an exemplary state of the 3D electronic book of FIG. 11 at the end of rotation of a rotating page block.</figref><figref num="23">It is a figure which draws an exemplary state of the 3D electronic book of FIG. 11 at the end of rotation of a rotating page block.</figref><figref num="24">It is a figure which draws an exemplary embodiment of the frame of the page turning animation at a certain time using the virtual geometry shape shown in FIG.</figref><figref num="25">It is a figure which draws an exemplary embodiment of the frame of a page turning animation at another time point using the virtual geometry shape shown in FIG.</figref><figref num="26">It is a schematic flowchart diagram of an exemplary method for turning pages of a three-dimensional electronic document.</figref><figref num="27A">An exemplary method of displaying a rotating page block with respect to the baseline and side coordinates of a virtual geometry object located in a plane perpendicular to the baseline of an open 3D electronic document (Note: Mainly corresponding to S1400 in Figure 26). This is a schematic flowchart of the left page block, the right page block, and the rotating page block based on the number of selected pages and animating the movement of the left page block, the right page block, and the rotating page block with respect to one page line and two geometric objects. is there.</figref><figref num="27B">An exemplary method of displaying a rotating page block with respect to the baseline and side coordinates of a virtual geometry object located in a plane perpendicular to the baseline of an open 3D electronic document (Note: Mainly corresponding to S1400 in Figure 26). This is a schematic flowchart of the left page block, the right page block, and the rotating page block based on the number of selected pages and animating the movement of the left page block, the right page block, and the rotating page block with respect to one page line and two geometric objects. is there.</figref><figref num="28">FIG. 6 is a schematic flowchart of an exemplary method for determining the coordinates of points on a left page block, a right page block, and a rotated page block.</figref><figref num="29">It is a schematic block diagram of an exemplary embodiment of a system that flips and displays pages of a three-dimensional electronic document.</figref>

Code description

600 Display, 700 User Input, 520 Controller, 510 Input / Output Interface, 530 Memory, 540 Page Block Determination Circuit, Routine, or Application, 500 Document Rotation Control System.