Graphics Programming
TVP4020
Programmers Reference Manual
94
all contributing pixels are accepted, and a varying alpha value where
some are rejected and some accepted. As the magnification factor of the
bilinear zoom is increased the variable alpha is spread across more
destination pixels. The range of alpha values rejected by the chroma key
test in the YUV unit can be adjusted to allow fine control over the exact
size of the cut-out. If blending is enabled then the varying alpha values
smooth the transition of the edge of the sprite to the background.
The registers AlphaMapUpperBound and AlphaMapLowerBound are
used to control the range over which the test is done. The test is enabled
by the TextureDataFormat register.
5.8.9
Texture Download Example
fbReadMode.PatchMode = PERMEDIA_TRUE
fbReadMode.SubPatchMode = PERMEDIA_SUBPATCH
FBReadMode(fbReadMode);
fbWriteMode.Enable = PERMEDIA_TRUE
FBWriteMode(fbWriteMode)
// Set format to 8 bits
ditherMode.UnitEnable = PERMEDIA_TRUE
ditherMode.Enable = PERMEDIA_FALSE
ditherMode.ColorMode = PERMEDIA_COLOR_FORMAT_RGB_332
DitherMode(ditherMode)
// Do image download
5.8.10
Texture Mapping Example
Texture map a trapezoid:
Содержание TVP4020 PERMEDIA 2
Страница 1: ...Texas Instruments TVP4020 PERMEDIA 2 Programmer s Reference Manual Issue 4 ...
Страница 47: ...Memory I O and Organization TVP4020 Programmers Reference Manual 38 Texture address TextureBaseAddress T W S ...
Страница 284: ...TVP4020 Programmers Reference Manual A Gouraud Shaded Triangle 275 ...
Страница 292: ...TVP4020 Programmers Reference Manual Register Tables 283 ...
Страница 314: ...TVP4020 Programmers Reference Manual Index 305 ...
Страница 315: ...Index TVP4020 Programmers Reference Manual 306 Index ...
Страница 323: ...Index TVP4020 Programmers Reference Manual 314 ...