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the canvas would still *feel* like a window. The shape of the jagged |
the canvas would still *feel* like a window. The shape of the jagged |
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edge must be tied to the location on the background[Fig.3]. |
edge must be tied to the location on the background[Fig.3]. |
15 |
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16 |
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XXX: |
17 |
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- only need texture_env_add which is included in OpenGL 1.3 |
18 |
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- no more accuracy with NV10 |
19 |
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- less accuracy without texture_env_add (using horrible projective |
20 |
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color interpolation (which the spec does not require to be |
21 |
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implemented) hack to compensate the nonlinearity of texenv_modulate) |
22 |
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- improved shapes? |
23 |
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24 |
We show how the GPU can be used to accomplish this - this is the easy |
We show how the GPU can be used to accomplish this - this is the easy |
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part and we can even do this on unextended OpenGL 1.3 (XXX jvk!), |
part and we can even do this on unextended OpenGL 1.3 (XXX jvk!), |
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although the flexibility of the NV10 architecture allows us to obtain |
although the flexibility of the NV10 architecture allows us to obtain |
31 |
draw smoothly interpolated polygons with a different color inside and |
draw smoothly interpolated polygons with a different color inside and |
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outside of the viewport. The pixel pipeline is coaxed to combining the |
outside of the viewport. The pixel pipeline is coaxed to combining the |
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interpolated value and the texture value into a single alpha value. |
interpolated value and the texture value into a single alpha value. |
34 |
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--- XXX: is the previous sentence correct?. |
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Because the alpha test is performed prior to the stencil test, we can |
Because the alpha test is performed prior to the stencil test, we can |
36 |
create the shape by rejecting fragments with the alpha test and drawing |
create the shape by rejecting fragments with the alpha test and drawing |
37 |
the remaining shape into the stencil buffer. Once the shape is in the |
the remaining shape into the stencil buffer. Once the shape is in the |