Program, information storage medium, image generation system, and image generation method for generating an image for overdriving the display device

1. A computer-readable information storage medium that stores a program for generating an image, the program causing a computer to function as:

a drawing section which draws an object to generate image data; and

an overdrive effect processing section which performs overdrive effect processing for the generated image data and generates image data to be output to a display section, wherein:

the overdrive effect processing section generates image data subjected to the overdrive effect processing by performing alpha blending which calculates IMK+(IMK−IMJ)×α based on image data IMK generated in a Kth frame, image data IMJ generated by drawing an object in a Jth frame (K>J), and an alpha value α, and

the overdrive effect processing section sets AS=(1=α)/2 in a double value mode in which a value twice a set value AS is set as a source alpha value A, sets BS=α in a fixed value mode in which a set value BS is set as a fixed destination alpha value B, and performs drawing while performing subtractive alpha blending which calculates IMK×A−IMJ×B=IMK×(2×AS)−IMJ×BS=IMK×(1+α)−IMJ×α.

2. The computer-readable information storage medium as defined in claim 1 ,

wherein the overdrive effect processing section adds image data obtained by multiplying the differential image data by an effect intensity coefficient to the image data generated in the Kth frame.

3. The computer-readable information storage medium as defined in claim 2 ,

wherein the overdrive effect processing section performs the overdrive effect processing based on the effect intensity coefficient which increases as a value of the differential image data increases.

4. The computer-readable information storage medium as defined in claim 1 ,

wherein the overdrive effect processing section stores difference reduction image data obtained based on the differential image data in the Kth frame, and performs the overdrive effect processing in an Lth (L>K>J) frame based on differential image data in the Lth frame which is differential image data between image data generated in the Lth frame and image data generated in the Kth frame and the stored difference reduction image data.

5. The computer-readable information storage medium as defined in claim 4 ,

wherein the overdrive effect processing section adds image data obtained by multiplying the differential image data in the Lth frame by the effect intensity coefficient and the stored difference reduction image data to the image data generated in the Lth frame.

6. The computer-readable information storage medium as defined in claim 1 ,

wherein the overdrive effect processing section performs the overdrive effect processing for only image data in a specific area of a display area of the display section.

7. The computer-readable information storage medium as defined in claim 1 ,

wherein the drawing section generates the image data by drawing a plurality of objects; and

wherein the overdrive effect processing section performs the overdrive effect processing for an area which involves a specific object included in the objects.

8. The computer-readable information storage medium as defined in claim 7 ,

wherein the overdrive effect processing section sets the area to perform the overdrive effect processing based on vertex coordinates of the objects, or, when a simple object is set for the objects, vertex coordinates of the simple object.

9. The computer-readable information storage medium as defined in claim 1 , the program causing the computer to function as:

a display control section which controls display of an adjustment screen for adjusting effect intensity of the overdrive effect processing,

wherein, when the effect intensity has been adjusted by using the adjustment screen, the overdrive effect processing section performs the overdrive effect processing based on the effect intensity after the adjustment.

10. The computer-readable information storage medium as defined in claim 9 ,

wherein the display control section moves an object set in a second intermediate color in a background area of the adjustment screen set in a first intermediate color.

11. The computer-readable information storage medium as defined in claim 1 , the program causing the computer to function as:

a display control section which controls display of a mode setting screen for setting whether or not to enable the overdrive effect processing,

wherein the overdrive effect processing section performs the overdrive effect processing when the overdrive effect processing has been enabled by using the mode setting screen.

12. The computer-readable information storage medium as defined in claim 1 ,

wherein the overdrive effect processing section maps a texture of the image data IMK onto a primitive plane with a screen size or a divided screen size in which the alpha value is set, and draws the primitive plane onto which the texture has been mapped in a buffer in which the image data IMJ has been drawn while performing alpha blending.

13. A computer-readable information storage medium that stores a program for generating an image, the program causing a computer to function as:

a drawing section which draws an object to generate image data; and

an overdrive effect processing section which performs overdrive effect processing for the generated image data and generates image data to be output to a display section, wherein:

the overdrive effect processing section generates image data subjected to the overdrive effect processing by performing alpha blending which calculates IMK+(IMK−IMJ)×α based on image data IMK generated in a Kth frame, image data IMJ generated by drawing an object in a Jth frame (K>J), and an alpha value α,

in the Kth frame, the overdrive effect processing section generates the image data IMK by drawing an object in a first buffer, and writes into a second buffer image data subjected to the overdrive effect processing by performing alpha blending which calculates IMK+(IMK−IMJ)×α based on the generated image data IMK, the image data IMJ in the Jth frame which has been written into the second buffer, and the alpha value α,

in an Lth frame, the overdrive effect processing section generates image data IML by drawing an object in a third buffer, and writes into the first buffer image data subjected to the overdrive effect processing by performing alpha blending which calculates IML+(IML−IMK)×α based on the generated image data IML, the image data IMK in the Kth frame which has been written into the first buffer, and the alpha value α, and

in an Mth frame (M>L>K), the overdrive effect processing section generates image data IMM by drawing an object in the second buffer, and writes into the third buffer image data subjected to the overdrive effect processing by performing alpha blending which calculates IMM+(IMM−IML)×α based on the generated image data IMM, the image data IML in the Lth frame which has been written into the third buffer, and the alpha value α.

14. The computer-readable information storage medium as defined in claim 13 ,

wherein the overdrive effect processing section adds image data obtained by multiplying the differential image data by an effect intensity coefficient to the image data generated in the Kth frame.

15. The computer-readable information storage medium as defined in claim 14 ,

wherein the overdrive effect processing section performs the overdrive effect processing based on the effect intensity coefficient which increases as a value of the differential image data increases.

16. The computer-readable information storage medium as defined in claim 13 ,

wherein the overdrive effect processing section stores difference reduction image data obtained based on the differential image data in the Kth frame, and performs the overdrive effect processing in an Lth (L>K>J) frame based on differential image data in the Lth frame which is differential image data between image data generated in the Lth frame and image data generated in the Kth frame and the stored difference reduction image data.

17. The computer-readable information storage medium as defined in claim 16 ,

wherein the overdrive effect processing section adds image data obtained by multiplying the differential image data in the Lth frame by the effect intensity coefficient and the stored difference reduction image data to the image data generated in the Lth frame.

18. The computer-readable information storage medium as defined in claim 13 ,

wherein the overdrive effect processing section performs the overdrive effect processing for only image data in a specific area of a display area of the display section.

19. The computer-readable information storage medium as defined in claim 13 ,

wherein the drawing section generates the image data by drawing a plurality of objects; and

wherein the overdrive effect processing section performs the overdrive effect processing for an area which involves a specific object included in the objects.

20. The computer-readable information storage medium as defined in claim 19 ,

wherein the overdrive effect processing section sets the area to perform the overdrive effect processing based on vertex coordinates of the objects, or, when a simple object is set for the objects, vertex coordinates of the simple object.

21. The computer-readable information storage medium as defined in claim 13 , the program causing the computer to function as:

a display control section which controls display of an adjustment screen for adjusting effect intensity of the overdrive effect processing,

wherein, when the effect intensity has been adjusted by using the adjustment screen, the overdrive effect processing section performs the overdrive effect processing based on the effect intensity after the adjustment.

22. The computer-readable information storage medium as defined in claim 21 ,

wherein the display control section moves an object set in a second intermediate color in a background area of the adjustment screen set in a first intermediate color.

23. The computer-readable information storage medium as defined in claim 13 , the program causing the computer to function as:

a display control section which controls display of a mode setting screen for setting whether or not to enable the overdrive effect processing,

wherein the overdrive effect processing section performs the overdrive effect processing when the overdrive effect processing has been enabled by using the mode setting screen.

24. The computer-readable information storage medium as defined in claim 13 ,

wherein the overdrive effect processing section maps a texture of the image data IMK onto a primitive plane with a screen size or a divided screen size in which the alpha value is set, and draws the primitive plane onto which the texture has been mapped in a buffer in which the image data IMJ has been drawn while performing alpha blending.