| | |
|---|
| | | unsigned long newtexlen; |
|---|
| | | unsigned int neww; |
|---|
| | | unsigned int newh; |
|---|
| | | unsigned int blocksize = 16; |
|---|
| | | uint32 blockDim = 1; |
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| | | uint32 blockSize = 0; |
|---|
| | | |
|---|
| | | if (glfmt == GL_COMPRESSED_RGBA_S3TC_DXT1_EXT) |
|---|
| | | { |
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| | | blocksize = 8; |
|---|
| | | switch (glfmt) { |
|---|
| | | case GL_COMPRESSED_RGBA_S3TC_DXT1_EXT: |
|---|
| | | blockDim = 4; |
|---|
| | | blockSize = 8; |
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| | | break; |
|---|
| | | |
|---|
| | | case GL_COMPRESSED_RGBA_S3TC_DXT3_EXT: |
|---|
| | | case GL_COMPRESSED_RGBA_S3TC_DXT5_EXT: |
|---|
| | | blockDim = 4; |
|---|
| | | blockSize = 16; |
|---|
| | | break; |
|---|
| | | |
|---|
| | | case GL_BGR: |
|---|
| | | blockSize = 3; |
|---|
| | | break; |
|---|
| | | |
|---|
| | | case GL_BGRA: |
|---|
| | | blockSize = 4; |
|---|
| | | break; |
|---|
| | | |
|---|
| | | case GL_LUMINANCE_ALPHA: |
|---|
| | | blockSize = 2; |
|---|
| | | break; |
|---|
| | | |
|---|
| | | default: |
|---|
| | | assert(!"unsupported GL format"); |
|---|
| | | break; |
|---|
| | | } |
|---|
| | | |
|---|
| | | assert(blockSize != 0); |
|---|
| | | |
|---|
| | | newtex = _basetex; |
|---|
| | | newtexlen = _basetexlen; |
|---|
| | |
|---|
| | | newh >>= 1; |
|---|
| | | if (neww < 1) neww = 1; |
|---|
| | | if (newh < 1) newh = 1; |
|---|
| | | newtexlen = ((neww + 3) / 4) * ((newh + 3) / 4) * blocksize; |
|---|
| | | newtexlen = ((neww + blockDim - 1) / blockDim) * ((newh + blockDim - 1) / blockDim) * blockSize; |
|---|
| | | } // for |
|---|
| | | |
|---|
| | | *_tex = newtex; |
|---|
