+#if 1
+// written by LordHavoc in a readable way, optimized by Vic, further optimized by LordHavoc (the non-special index case), readable version preserved below this
+void Image_CopyMux(qbyte *outpixels, const qbyte *inpixels, int inputwidth, int inputheight, qboolean inputflipx, qboolean inputflipy, qboolean inputflipdiagonal, int numoutputcomponents, int numinputcomponents, int *outputinputcomponentindices)
+{
+ int index, c, x, y;
+ const qbyte *in, *line;
+ int row_inc = (inputflipy ? -inputwidth : inputwidth) * numinputcomponents, col_inc = (inputflipx ? -1 : 1) * numinputcomponents;
+ int row_ofs = (inputflipy ? (inputheight - 1) * inputwidth * numinputcomponents : 0), col_ofs = (inputflipx ? (inputwidth - 1) * numinputcomponents : 0);
+
+ for (c = 0; c < numoutputcomponents; c++)
+ if (outputinputcomponentindices[c] & 0x80000000)
+ break;
+ if (c < numoutputcomponents)
+ {
+ // special indices used
+ if (inputflipdiagonal)
+ {
+ for (x = 0, line = inpixels + col_ofs; x < inputwidth; x++, line += col_inc)
+ for (y = 0, in = line + row_ofs; y < inputheight; y++, in += row_inc, outpixels += numinputcomponents)
+ for (c = 0; c < numoutputcomponents; c++)
+ outpixels[c] = ((index = outputinputcomponentindices[c]) & 0x80000000) ? index : in[index];
+ }
+ else
+ {
+ for (y = 0, line = inpixels + row_ofs; y < inputheight; y++, line += row_inc)
+ for (x = 0, in = line + col_ofs; x < inputwidth; x++, in += col_inc, outpixels += numinputcomponents)
+ for (c = 0; c < numoutputcomponents; c++)
+ outpixels[c] = ((index = outputinputcomponentindices[c]) & 0x80000000) ? index : in[index];
+ }
+ }
+ else
+ {
+ // special indices not used
+ if (inputflipdiagonal)
+ {
+ for (x = 0, line = inpixels + col_ofs; x < inputwidth; x++, line += col_inc)
+ for (y = 0, in = line + row_ofs; y < inputheight; y++, in += row_inc, outpixels += numinputcomponents)
+ for (c = 0; c < numoutputcomponents; c++)
+ outpixels[c] = in[outputinputcomponentindices[c]];
+ }
+ else
+ {
+ for (y = 0, line = inpixels + row_ofs; y < inputheight; y++, line += row_inc)
+ for (x = 0, in = line + col_ofs; x < inputwidth; x++, in += col_inc, outpixels += numinputcomponents)
+ for (c = 0; c < numoutputcomponents; c++)
+ outpixels[c] = in[outputinputcomponentindices[c]];
+ }
+ }
+}
+#else
+// intentionally readable version