| 0,0 → 1,121 |
|---|
| { |
| int n, dx, dy, sx, pp_inc_1, pp_inc_2; |
| register int a; |
| register PIXEL *pp; |
| #if defined(INTERP_RGB) || TGL_FEATURE_RENDER_BITS == 24 |
| register unsigned int r, g, b; |
| #endif |
| #ifdef INTERP_RGB |
| register unsigned int rinc, ginc, binc; |
| #endif |
| #ifdef INTERP_Z |
| register unsigned short *pz; |
| int zinc; |
| register int z, zz; |
| #endif |
| |
| if (p1->y > p2->y || (p1->y == p2->y && p1->x > p2->x)) { |
| ZBufferPoint *tmp; |
| tmp = p1; |
| p1 = p2; |
| p2 = tmp; |
| } |
| sx = zb->xsize; |
| pp = (PIXEL *) ((char *) zb->pbuf + zb->linesize * p1->y + p1->x * PSZB); |
| #ifdef INTERP_Z |
| pz = zb->zbuf + (p1->y * sx + p1->x); |
| z = p1->z; |
| #endif |
| |
| dx = p2->x - p1->x; |
| dy = p2->y - p1->y; |
| #ifdef INTERP_RGB |
| r = p1->r << 8; |
| g = p1->g << 8; |
| b = p1->b << 8; |
| #elif TGL_FEATURE_RENDER_BITS == 24 |
| /* for 24 bits, we store the colors in different variables */ |
| r = p2->r >> 8; |
| g = p2->g >> 8; |
| b = p2->b >> 8; |
| #endif |
| |
| #ifdef INTERP_RGB |
| #define RGB(x) x |
| #if TGL_FEATURE_RENDER_BITS == 24 |
| #define RGBPIXEL pp[0] = r >> 16, pp[1] = g >> 16, pp[2] = b >> 16 |
| #else |
| #define RGBPIXEL *pp = RGB_TO_PIXEL(r >> 8,g >> 8,b >> 8) |
| #endif |
| #else /* INTERP_RGB */ |
| #define RGB(x) |
| #if TGL_FEATURE_RENDER_BITS == 24 |
| #define RGBPIXEL pp[0] = r, pp[1] = g, pp[2] = b |
| #else |
| #define RGBPIXEL *pp = color |
| #endif |
| #endif /* INTERP_RGB */ |
| |
| #ifdef INTERP_Z |
| #define ZZ(x) x |
| #define PUTPIXEL() \ |
| { \ |
| zz=z >> ZB_POINT_Z_FRAC_BITS; \ |
| if (ZCMP(zz,*pz)) { \ |
| RGBPIXEL; \ |
| *pz=zz; \ |
| } \ |
| } |
| #else /* INTERP_Z */ |
| #define ZZ(x) |
| #define PUTPIXEL() RGBPIXEL |
| #endif /* INTERP_Z */ |
| |
| #define DRAWLINE(dx,dy,inc_1,inc_2) \ |
| n=dx;\ |
| ZZ(zinc=(p2->z-p1->z)/n);\ |
| RGB(rinc=((p2->r-p1->r) << 8)/n;\ |
| ginc=((p2->g-p1->g) << 8)/n;\ |
| binc=((p2->b-p1->b) << 8)/n);\ |
| a=2*dy-dx;\ |
| dy=2*dy;\ |
| dx=2*dx-dy;\ |
| pp_inc_1 = (inc_1) * PSZB;\ |
| pp_inc_2 = (inc_2) * PSZB;\ |
| do {\ |
| PUTPIXEL();\ |
| ZZ(z+=zinc);\ |
| RGB(r+=rinc;g+=ginc;b+=binc);\ |
| if (a>0) { pp=(PIXEL *)((char *)pp + pp_inc_1); ZZ(pz+=(inc_1)); a-=dx; }\ |
| else { pp=(PIXEL *)((char *)pp + pp_inc_2); ZZ(pz+=(inc_2)); a+=dy; }\ |
| } while (--n >= 0); |
| |
| /* fin macro */ |
| |
| if (dx == 0 && dy == 0) { |
| PUTPIXEL(); |
| } else if (dx > 0) { |
| if (dx >= dy) { |
| DRAWLINE(dx, dy, sx + 1, 1); |
| } else { |
| DRAWLINE(dy, dx, sx + 1, sx); |
| } |
| } else { |
| dx = -dx; |
| if (dx >= dy) { |
| DRAWLINE(dx, dy, sx - 1, -1); |
| } else { |
| DRAWLINE(dy, dx, sx - 1, sx); |
| } |
| } |
| } |
| |
| #undef INTERP_Z |
| #undef INTERP_RGB |
| |
| /* internal defines */ |
| #undef DRAWLINE |
| #undef PUTPIXEL |
| #undef ZZ |
| #undef RGB |
| #undef RGBPIXEL |