X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?a=blobdiff_plain;f=src%2Fpolyfill.c;h=1393cd200fc0b1b1906f51236cf229adb966d344;hb=0065a39b46f7f9ae394e75a6c3d661e48e995045;hp=7bffaa35690460fbdaa12d7e30b9f1337612a936;hpb=3616caf014bccbf8814a67cf87ac012a91e7e968;p=dosdemo

diff --git a/src/polyfill.c b/src/polyfill.c
index 7bffaa3..1393cd2 100644
--- a/src/polyfill.c
+++ b/src/polyfill.c
@@ -2,7 +2,11 @@
 #include <stdlib.h>
 #include <string.h>
 #include <assert.h>
+#if defined(__WATCOMC__) || defined(_MSC_VER) || defined(__DJGPP__)
+#include <malloc.h>
+#else
 #include <alloca.h>
+#endif
 #include "polyfill.h"
 #include "gfxutil.h"
 #include "demo.h"
@@ -10,10 +14,12 @@
 void (*fillfunc[])(struct pvertex*, int) = {
 	polyfill_wire,
 	polyfill_flat,
-	0, 0, 0
+	polyfill_gouraud,
+	polyfill_tex,
+	polyfill_tex_gouraud
 };
 
-struct pimage pimg_fb, pimg_texture;
+struct pimage pfill_fb, pfill_tex;
 
 void polyfill(int mode, struct pvertex *verts, int nverts)
 {
@@ -40,95 +46,63 @@ void polyfill_wire(struct pvertex *verts, int nverts)
 		++v;
 		x1 = v->x >> 8;
 		y1 = v->y >> 8;
-		if(clip_line(&x0, &y0, &x1, &y1, 0, 0, pimg_fb.width, pimg_fb.height)) {
+		if(clip_line(&x0, &y0, &x1, &y1, 0, 0, pfill_fb.width, pfill_fb.height)) {
 			draw_line(x0, y0, x1, y1, color);
 		}
 	}
 	x0 = verts[0].x >> 8;
 	y0 = verts[0].y >> 8;
-	if(clip_line(&x1, &y1, &x0, &y0, 0, 0, pimg_fb.width, pimg_fb.height)) {
+	if(clip_line(&x1, &y1, &x0, &y0, 0, 0, pfill_fb.width, pfill_fb.height)) {
 		draw_line(x1, y1, x0, y0, color);
 	}
 }
 
-static void scan_edge(struct pvertex *v0, struct pvertex *v1, struct pvertex *edge);
-
 #define NEXTIDX(x) (((x) - 1 + nverts) % nverts)
 #define PREVIDX(x) (((x) + 1) % nverts)
 
-void polyfill_flat(struct pvertex *pv, int nverts)
-{
-	int i;
-	int32_t y;
-	int topidx = 0, botidx = 0, sline;
-	struct pvertex *left, *right;
-	/*uint16_t color = PACK_RGB16(pv[0].r, pv[0].g, pv[0].b);*/
-
-	for(i=1; i<nverts; i++) {
-		if(pv[i].y < pv[topidx].y) topidx = i;
-		if(pv[i].y > pv[botidx].y) botidx = i;
-	}
-
-	left = (struct pvertex*)alloca(pimg_fb.height * sizeof *left);
-	right = (struct pvertex*)alloca(pimg_fb.height * sizeof *right);
-	memset(left, 0, pimg_fb.height * sizeof *left);
-	memset(right, 0, pimg_fb.height * sizeof *right);
-
-	for(i=0; i<nverts; i++) {
-		int next = NEXTIDX(i);
-		int32_t y0 = pv[i].y;
-		int32_t y1 = pv[next].y;
-
-		if((y0 >> 8) == (y1 >> 8)) {
-			if(y0 > y1) {
-				int idx = y0 >> 8;
-				left[idx].x = pv[i].x < pv[next].x ? pv[i].x : pv[next].x;
-				right[idx].x = pv[i].x < pv[next].x ? pv[next].x : pv[i].x;
-			}
-		} else {
-			scan_edge(pv + i, pv + next, y0 > y1 ? left : right);
-		}
-	}
-
-	y = pv[topidx].y;
-	while(y < pv[botidx].y) {
-		int32_t x;
-		uint16_t *pixptr;
-
-		sline = y >> 8;
-		x = left[sline].x;
-
-		pixptr = pimg_fb.pixels + sline * pimg_fb.width + (x >> 8);
-
-		while(x <= right[sline].x) {
-			*pixptr++ += 15;
-			x += 256;
-		}
-		y += 256;
-	}
-}
-
-static void scan_edge(struct pvertex *v0, struct pvertex *v1, struct pvertex *edge)
-{
-	int32_t x, y, dx, dy, slope;
-	int idx;
-
-	if(v0->y > v1->y) {
-		struct pvertex *tmp = v0;
-		v0 = v1;
-		v1 = tmp;
-	}
-
-	dy = v1->y - v0->y;
-	dx = v1->x - v0->x;
-	slope = (dx << 8) / dy;
-	idx = v0->y >> 8;
-
-	x = v0->x;
-	y = v0->y;
-	while(y <= v1->y) {
-		edge[idx++].x = x;
-		x += slope;
-		y += 256;
-	}
-}
+/* XXX
+ * When HIGH_QUALITY is defined, the rasterizer calculates slopes for attribute
+ * interpolation on each scanline separately; otherwise the slope for each
+ * attribute would be calculated once for the whole polygon, which is faster,
+ * but produces some slight quantization artifacts, due to the limited precision
+ * of fixed-point calculations.
+ */
+#define HIGH_QUALITY
+
+/* extra bits of precision to use when interpolating colors.
+ * try tweaking this if you notice strange quantization artifacts.
+ */
+#define COLOR_SHIFT	12
+
+
+#define POLYFILL polyfill_flat
+#define SCANEDGE scanedge_flat
+#undef GOURAUD
+#undef TEXMAP
+#include "polytmpl.h"
+#undef POLYFILL
+#undef SCANEDGE
+
+#define POLYFILL polyfill_gouraud
+#define SCANEDGE scanedge_gouraud
+#define GOURAUD
+#undef TEXMAP
+#include "polytmpl.h"
+#undef POLYFILL
+#undef SCANEDGE
+
+#define POLYFILL polyfill_tex
+#define SCANEDGE scanedge_tex
+#undef GOURAUD
+#define TEXMAP
+#include "polytmpl.h"
+#undef POLYFILL
+#undef SCANEDGE
+
+#define POLYFILL polyfill_tex_gouraud
+#define SCANEDGE scanedge_tex_gouraud
+#define GOURAUD
+#define TEXMAP
+#include "polytmpl.h"
+#undef POLYFILL
+#undef SCANEDGE