--- /dev/null
+#ifdef _MSC_VER
+#pragma warning (disable: 4101)
+#endif
+
+#if !defined(GOURAUD) && !defined(TEXMAP) && !defined(ZBUF)
+#define NOLERP
+#endif
+
+void POLYFILL(struct pvertex *varr)
+{
+ int i, line, top, bot;
+ struct pvertex *v, *vn, *tab;
+ int32_t x, y0, y1, dx, dy, slope, fx, fy;
+ int start, len;
+ g3d_pixel *fbptr, *pptr, color;
+#ifdef GOURAUD
+ int32_t lum, dl, lumslope;
+#endif /* GOURAUD */
+#ifdef TEXMAP
+ int32_t tu, tv, du, dv, uslope, vslope;
+ int tx, ty;
+ g3d_pixel texel;
+#endif
+#ifdef ZBUF
+ int32_t z, dz, zslope;
+ uint32_t *zptr;
+#endif
+
+#if !defined(GOURAUD)
+ /* for flat shading we already know the intensity */
+ color = find_color(varr[0].l, varr[0].l, varr[0].l);
+#endif
+
+ top = pfill_fb.height;
+ bot = 0;
+
+ for(i=0; i<3; i++) {
+ /* scan the edge between the current and next vertex */
+ v = varr + i;
+ vn = VNEXT(v);
+
+ if(vn->y == v->y) continue; /* XXX ??? */
+
+ if(vn->y >= v->y) {
+ /* inrementing Y: left side */
+ tab = left;
+ } else {
+ /* decrementing Y: right side, flip vertices to trace bottom->up */
+ tab = right;
+ v = vn;
+ vn = varr + i;
+ }
+
+ /* calculate edge slope */
+ dx = vn->x - v->x;
+ dy = vn->y - v->y;
+ slope = (dx << 8) / dy;
+
+#ifdef GOURAUD
+ lum = v->l << COLOR_SHIFT;
+ dl = (vn->l << COLOR_SHIFT) - lum;
+ lumslope = (dl << 8) / dy;
+#endif /* GOURAUD */
+#ifdef TEXMAP
+ tu = v->u;
+ tv = v->v;
+ du = vn->u - tu;
+ dv = vn->v - tv;
+ uslope = (du << 8) / dy;
+ vslope = (dv << 8) / dy;
+#endif /* TEXMAP */
+#ifdef ZBUF
+ z = v->z;
+ dz = vn->z - z;
+ zslope = (dz << 8) / dy;
+#endif /* ZBUF */
+
+ y0 = (v->y + 0x100) & 0xffffff00; /* start from the next scanline */
+ fy = y0 - v->y; /* fractional part before the next scanline */
+ fx = (fy * slope) >> 8; /* X adjust for the step to the next scanline */
+ x = v->x + fx; /* adjust X */
+ y1 = vn->y & 0xffffff00; /* last scanline of the edge <= vn->y */
+
+ /* also adjust other interpolated attributes */
+#ifdef GOURAUD
+ lum += (fy * lumslope) >> 8;
+#endif /* GOURAUD */
+#ifdef TEXMAP
+#ifdef FLTUV
+ tu += uslope * (fy / 256.0f);
+ tv += vslope * (fy / 256.0f);
+#else
+ tu += (fy * uslope) >> 8;
+ tv += (fy * vslope) >> 8;
+#endif
+#endif /* TEXMAP */
+#ifdef ZBUF
+ z += (fy * zslope) >> 8;
+#endif
+
+ line = y0 >> 8;
+ if(line < top) top = line;
+ if((y1 >> 8) > bot) bot = y1 >> 8;
+
+ if(line > 0) tab += line;
+
+ while(line <= (y1 >> 8) && line < pfill_fb.height) {
+ if(line >= 0) {
+ int val = x < 0 ? 0 : x >> 8;
+ tab->x = val < pfill_fb.width ? val : pfill_fb.width - 1;
+#ifdef GOURAUD
+ tab->l = lum;
+#endif /* GOURAUD */
+#ifdef TEXMAP
+ tab->u = tu;
+ tab->v = tv;
+#endif /* TEXMAP */
+#ifdef ZBUF
+ tab->z = z;
+#endif
+ tab++;
+ }
+ x += slope;
+#ifdef GOURAUD
+ lum += lumslope;
+#endif /* GOURAUD */
+#ifdef TEXMAP
+ tu += uslope;
+ tv += vslope;
+#endif /* TEXMAP */
+#ifdef ZBUF
+ z += zslope;
+#endif /* ZBUF */
+ line++;
+ }
+ }
+
+ if(top < 0) top = 0;
+ if(bot >= pfill_fb.height) bot = pfill_fb.height - 1;
+
+ fbptr = pfill_fb.pixels + top * pfill_fb.width;
+ for(i=top; i<=bot; i++) {
+ start = left[i].x;
+ len = right[i].x - start;
+ /* XXX we probably need more precision in left/right.x */
+
+#ifndef NOLERP
+ dx = len == 0 ? 256 : (len << 8);
+#endif
+
+#ifdef GOURAUD
+ lum = left[i].l;
+#endif /* GOURAUD */
+#ifdef TEXMAP
+ tu = left[i].u;
+ tv = left[i].v;
+#endif /* TEXMAP */
+#ifdef ZBUF
+ z = left[i].z;
+ zptr = pfill_zbuf + i * pfill_fb.width + start;
+#endif /* ZBUF */
+
+ pptr = fbptr + start;
+ while(len-- > 0) {
+#if defined(GOURAUD) || defined(TEXMAP)
+ int inten;
+#endif
+#ifdef ZBUF
+ uint32_t cz = z;
+ z += pgrad.dzdx;
+
+ if(cz <= *zptr) {
+ *zptr++ = cz;
+ } else {
+ /* ZFAIL: advance all attributes and continue */
+#ifdef GOURAUD
+ lum += pgrad.dldx;
+#endif /* GOURAUD */
+#ifdef TEXMAP
+ tu += pgrad.dudx;
+ tv += pgrad.dvdx;
+#endif /* TEXMAP */
+ /* skip pixel */
+ pptr++;
+ zptr++;
+ continue;
+ }
+#endif /* ZBUF */
+
+#ifdef GOURAUD
+ /* we upped the color precision to while interpolating the
+ * edges, now drop the extra bits before packing
+ */
+ inten = lum < 0 ? 0 : (lum >> COLOR_SHIFT);
+ lum += pgrad.dldx;
+#endif /* GOURAUD */
+#ifdef TEXMAP
+ tx = (tu >> (16 - pfill_tex.xshift)) & pfill_tex.xmask;
+ ty = (tv >> (16 - pfill_tex.yshift)) & pfill_tex.ymask;
+ texel = pfill_tex.pixels[(ty << pfill_tex.xshift) + tx];
+
+ tu += pgrad.dudx;
+ tv += pgrad.dvdx;
+
+#ifndef GOURAUD
+ /* for flat textured, cr,cg,cb would not be initialized */
+ inten = varr[0].l;
+#endif /* !GOURAUD */
+ /* This is not correct, should be /255, but it's much faster
+ * to shift by 8 (/256), and won't make a huge difference
+ */
+ color = shade_color(texel, inten);
+#endif /* TEXMAP */
+
+#ifdef DEBUG_OVERDRAW
+ *pptr++ += DEBUG_OVERDRAW;
+#else
+#if defined(GOURAUD) || defined(TEXMAP)
+ if(inten >= 255) inten = 255;
+ color = find_color(inten, inten, inten);
+#endif
+ *pptr++ = color;
+#endif
+ }
+ fbptr += pfill_fb.width;
+ }
+}
+
+#undef NOLERP
projects / metatoy / blobdiff