diff options
Diffstat (limited to 'source/dsp2emu.c')
| -rw-r--r-- | source/dsp2emu.c | 26 |
1 files changed, 8 insertions, 18 deletions
diff --git a/source/dsp2emu.c b/source/dsp2emu.c index d5a9855..1ec79bc 100644 --- a/source/dsp2emu.c +++ b/source/dsp2emu.c @@ -136,29 +136,19 @@ int DSP2Op0DInLen = 0; void DSP2_Op0D() { - // Overload's algorithm - use this unless doing hardware testing - - // One note: the HW can do odd byte scaling but since we divide - // by two to get the count of bytes this won't work well for - // odd byte scaling (in any of the current algorithm implementations). - // So far I haven't seen Dungeon Master use it. - // If it does we can adjust the parameters and code to work with it + // (Modified) Overload's algorithm - use this unless doing hardware testing int i; - int pixel_offset; - uint8_t pixelarray[512]; - for (i = 0; i < DSP2Op0DOutLen * 2; i++) + for(i = 0 ; i < DSP2Op0DOutLen ; i++) { - pixel_offset = (i * DSP2Op0DInLen) / DSP2Op0DOutLen; - if ((pixel_offset & 1) == 0) - pixelarray[i] = DSP1.parameters[pixel_offset >> 1] >> 4; - else - pixelarray[i] = DSP1.parameters[pixel_offset >> 1] & 0x0f; + int j = i << 1; + int pixel_offset_low = ((j * DSP2Op0DInLen) / DSP2Op0DOutLen) >> 1; + int pixel_offset_high = (((j + 1) * DSP2Op0DInLen) / DSP2Op0DOutLen) >> 1; + uint8_t pixel_low = DSP1.parameters[pixel_offset_low] >> 4; + uint8_t pixel_high = DSP1.parameters[pixel_offset_high] & 0x0f; + DSP1.output[i] = (pixel_low << 4) | pixel_high; } - - for (i = 0; i < DSP2Op0DOutLen; i++) - DSP1.output[i] = (pixelarray[i << 1] << 4) | pixelarray[(i << 1) + 1]; } #else |