Subpixel compositing on transparent backgrounds

1. A method for displaying a rendered image on an electronic computing device, the method comprising:

rendering a first image of an object on the electronic computing device, the first image being rendered on a white background;

rendering a second image of the object on the electronic computing device, the second image being rendered on a black background;

storing a data value for each of a plurality of pixels in the rendered first image and the rendered second image, the data value comprising a plurality of subpixel color values and a pixel opacity value;

combining the first image, the second image and a background image to produce a third image, the third image being a composite of the first image, the second image and the background image; and

displaying the third image on a display screen of the electronic computing device, wherein the third image includes anti-aliasing for a plurality of subpixels of the third image, the anti-aliasing comprising a determination of opacity and intensity values for each of the plurality of subpixels, the opacity values for each of the plurality of subpixels being determined utilizing the stored data value.

2. The method of claim 1 , wherein the third image is moved to a plurality of positions on the display screen, the third image including anti-aliasing for the plurality of subpixels of the third image at each of the plurality of positions on the display screen.

3. The method of claim 1 , wherein combining the first image, the second image and a background image to produce a third image comprises subtracting a subpixel color value for the second image from a subpixel color value for the first image for a plurality of subpixels of the first image and the second image.

4. The method of claim 3 , wherein the result of each subtraction is equal to one minus an opacity.

5. The method of claim 3 , further comprising multiplying the result of the subtraction by a color value for the background image corresponding to the subpixel.

6. The method of claim 5 , further comprising calculating an output value for the subpixel, the output value being a subpixel color value for displaying the subpixel on the display screen, the output value for the subpixel being equal to the sum of 1) the multiplication of the result of the subtraction by the color value for the background image corresponding to the subpixel and 2) a subpixel color value for the second image corresponding to the subpixel.

7. The method of claim 6 , wherein the output value for the subpixel is represented by the equation:

output=background*( W−B )+ B

where, background is a color value of a subpixel in the background image,

W is a color value for the subpixel in the first image,

B is a color value for the subpixel in the second image.

8. The method of claim 1 , wherein the background image comprises a background pattern on the display screen.

9. The method of claim 8 , wherein the background pattern is static.

10. The method of claim 8 , wherein the background pattern is dynamic.

11. An electronic computing device comprising:

a processing unit; and

system memory, the system memory including instructions that, when executed by the processing unit, cause the electronic computing device to:

render a first image of an object on the electronic computing device, the first image being rendered on a white background;

render a second image of the object on the electronic computing device, the second image being rendered on a black background;

store a data value for each of a plurality of pixels in the rendered first image and the rendered second image, the data value comprising a plurality of subpixel color values and a pixel opacity value;

combine the first image, the second image and a background image to produce a third image, the third image being a composite of the first image, the second image and the background image; and

display the third image on a display screen of the electronic computing device, wherein the third image includes anti-aliasing for a plurality of subpixels of the third image, the anti-aliasing comprising a determination of opacity and intensity values for each of the plurality of subpixels, the opacity values for each of the plurality of subpixels being determined utilizing the stored data value.

12. The electronic computing device of claim 11 , wherein the third image is moved to a plurality of positions on the display screen, the third image including anti-aliasing for the plurality of subpixels of the third image at each of the plurality of positions on the display screen.

13. The electronic computing device of claim 11 , wherein combining the first image, the second image and a background image to produce a third image causing the electronic computing device to:

subtract a subpixel color value for the second image from a subpixel color value for the first image;

multiply the result of the subtraction by a color value for the background image corresponding to the subpixel; and

calculate an output value for the subpixel, the output value being a subpixel color value for displaying the subpixel on the display screen, the output value for the subpixel being equal to the sum of 1) the multiplication of the result of the subtraction by the color value for the background image and 2) a subpixel color value for the second image corresponding to the subpixel.

14. The electronic computing device of claim 13 , wherein the output value for the subpixel is represented by the equation:

output=background*( W−B )+ B

where, background is a color level of the subpixel corresponding to the background display,

W is a color value for the subpixel for the first image,

B is a color value for the subpixel for the second image.

15. The electronic computing device of claim 13 , wherein the result of subtracting the subpixel color value for the second image from the subpixel color value for the first image is equal to one minus an opacity for the subpixel.

16. The electronic computing device of claim 13 , wherein the background image comprises a background pattern on the display screen.

17. A computer readable storage device comprising instructions that, when executed by an electronic computing device, cause the electronic computing device to:

render a first image of an object on the electronic computing device, the first image being rendered on a white background;

render a second image of the object on the electronic computing device, the second image being rendered on a black background;

store a data value for each of a plurality of pixels in the rendered first image and the rendered second image, the data value comprising a plurality of subpixel color values and a pixel opacity value;

combine the first image, the second image and a background image to produce a third image, the third image being a composite of the first image, the second image and the background image, the background image comprising a pattern on the display screen, the combining of the first image, the second image and a background image to produce a third image causing the electronic computing device to:

subtract a subpixel color value for the second image from a subpixel color value for the first image for a plurality of subpixels of the first image and the second image, the result of each subtraction being equal to one minus an opacity for the subpixel;

multiply the result of the subtraction by a color value for the background image corresponding to the subpixel; and

calculate an output value for the subpixel, the output value being a subpixel intensity level for displaying the subpixel on the display screen, the output value for the subpixel being equal to the sum of 1) the multiplication of the result of the subtraction by the color value for the background image and 2) a subpixel color value for the second image corresponding to the subpixel; and

display the third image at a plurality of positions on a display screen of the electronic computing device,

wherein the third image includes anti-aliasing for a plurality of subpixels of the third image at each of the plurality of positions on the display screen, the anti-aliasing comprising a determination of opacity and intensity values for each of the plurality of subpixel, the opacity values for each of the plurality of subpixels being determined utilizing the stored data value.