diff options
| -rw-r--r-- | src/r_draw.c | 111 |
1 files changed, 61 insertions, 50 deletions
diff --git a/src/r_draw.c b/src/r_draw.c index 6813ea59..b7d847d9 100644 --- a/src/r_draw.c +++ b/src/r_draw.c @@ -594,48 +594,54 @@ int dscount; // Draws the actual span. void R_DrawSpan (void) { - fixed_t xfrac; - fixed_t yfrac; - byte* dest; - int count; - int spot; - -#ifdef RANGECHECK + unsigned int position, step; + byte *dest; + int count; + int spot; + unsigned int xtemp, ytemp; + +#ifdef RANGECHECK if (ds_x2 < ds_x1 || ds_x1<0 - || ds_x2>=SCREENWIDTH + || ds_x2>=SCREENWIDTH || (unsigned)ds_y>SCREENHEIGHT) { I_Error( "R_DrawSpan: %i to %i at %i", ds_x1,ds_x2,ds_y); } -// dscount++; -#endif +// dscount++; +#endif + + // Pack position and step variables into a single 32-bit integer, + // with x in the top 16 bits and y in the bottom 16 bits. For + // each 16-bit part, the top 6 bits are the integer part and the + // bottom 10 bits are the fractional part of the pixel position. + + position = ((ds_xfrac << 10) & 0xffff0000) + | ((ds_yfrac >> 6) & 0x0000ffff); + step = ((ds_xstep << 10) & 0xffff0000) + | ((ds_ystep >> 6) & 0x0000ffff); - - xfrac = ds_xfrac; - yfrac = ds_yfrac; - dest = ylookup[ds_y] + columnofs[ds_x1]; // We do not check for zero spans here? - count = ds_x2 - ds_x1; + count = ds_x2 - ds_x1; - do + do { - // Current texture index in u,v. - spot = ((yfrac>>(16-6))&(63*64)) + ((xfrac>>16)&63); + // Calculate current texture index in u,v. + ytemp = (position >> 4) & 0x0fc0; + xtemp = (position >> 26); + spot = xtemp | ytemp; // Lookup pixel from flat texture tile, // re-index using light/colormap. *dest++ = ds_colormap[ds_source[spot]]; - // Next step in u,v. - xfrac += ds_xstep; - yfrac += ds_ystep; - - } while (count--); -} + position += step; + + } while (count--); +} @@ -715,49 +721,54 @@ void R_DrawSpan (void) // // Again.. // -void R_DrawSpanLow (void) -{ - fixed_t xfrac; - fixed_t yfrac; - byte* dest; - int count; - int spot; - -#ifdef RANGECHECK +void R_DrawSpanLow (void) +{ + unsigned int position, step; + unsigned int xtemp, ytemp; + byte *dest; + int count; + int spot; + +#ifdef RANGECHECK if (ds_x2 < ds_x1 || ds_x1<0 - || ds_x2>=SCREENWIDTH + || ds_x2>=SCREENWIDTH || (unsigned)ds_y>SCREENHEIGHT) { I_Error( "R_DrawSpan: %i to %i at %i", ds_x1,ds_x2,ds_y); } // dscount++; -#endif - - xfrac = ds_xfrac; - yfrac = ds_yfrac; - - count = (ds_x2 - ds_x1); +#endif + + position = ((ds_xfrac << 10) & 0xffff0000) + | ((ds_yfrac >> 6) & 0x0000ffff); + step = ((ds_xstep << 10) & 0xffff0000) + | ((ds_ystep >> 6) & 0x0000ffff); + + count = (ds_x2 - ds_x1); // Blocky mode, need to multiply by 2. ds_x1 <<= 1; ds_x2 <<= 1; - + dest = ylookup[ds_y] + columnofs[ds_x1]; - - do - { - spot = ((yfrac>>(16-6))&(63*64)) + ((xfrac>>16)&63); + + do + { + // Calculate current texture index in u,v. + ytemp = (position >> 4) & 0x0fc0; + xtemp = (position >> 26); + spot = xtemp | ytemp; + // Lowres/blocky mode does it twice, // while scale is adjusted appropriately. - *dest++ = ds_colormap[ds_source[spot]]; *dest++ = ds_colormap[ds_source[spot]]; - - xfrac += ds_xstep; - yfrac += ds_ystep; + *dest++ = ds_colormap[ds_source[spot]]; - } while (count--); + position += step; + + } while (count--); } // |