mirror of https://github.com/bsnes-emu/bsnes.git
30 lines
814 B
C++
30 lines
814 B
C++
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auto VDC::Background::scanline(uint y) -> void {
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}
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auto VDC::Background::run(uint x, uint y) -> void {
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color = nothing;
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//if(blank) return;
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uint10 hoffset = x + hscroll;
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uint9 voffset = y + vscroll;
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uint16 batAddress = (voffset >> 3) * width + (hoffset >> 3);
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uint16 tiledata = vdc.vramRead(batAddress);
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uint16 patternAddress = tiledata.bits(0,11) << 4;
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patternAddress += (voffset & 7);
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uint4 palette = tiledata.bits(12,15);
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uint16 d0 = vdc.vramRead(patternAddress + 0);
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uint16 d1 = vdc.vramRead(patternAddress + 8);
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uint3 index = 7 - (hoffset & 7);
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uint4 output;
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output.bit(0) = d0.bit(0 + index);
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output.bit(1) = d0.bit(8 + index);
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output.bit(2) = d1.bit(0 + index);
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output.bit(3) = d1.bit(8 + index);
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if(output == 0) return;
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color = vdc.cram[palette << 4 | output];
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}
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