#include <stdio.h>
#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"
+#define FILL_POLY_BITS 0x03
+
+/* mode bits: 00-wire 01-flat 10-gouraud 11-reserved
+ * bit 2: texture
+ * bit 3: blend
+ */
void (*fillfunc[])(struct pvertex*, int) = {
polyfill_wire,
polyfill_flat,
- 0, 0, 0
+ polyfill_gouraud,
+ 0,
+ polyfill_tex_wire,
+ polyfill_tex_flat,
+ polyfill_tex_gouraud,
+ 0,
+ polyfill_blend_wire,
+ polyfill_blend_flat,
+ polyfill_blend_gouraud,
+ 0,
+ polyfill_blend_tex_wire,
+ polyfill_blend_tex_flat,
+ polyfill_blend_tex_gouraud,
+ 0
};
-struct pimage pimg_fb, pimg_texture;
+struct pimage pfill_fb, pfill_tex;
void polyfill(int mode, 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);
}
}
-#define NEXTIDX(x) (((x) - 1 + nverts) % nverts)
-#define PREVIDX(x) (((x) + 1) % nverts)
-
-#define CALC_EDGE(which) \
- do { \
- which##_x = pv[which##_beg].x; \
- which##_dx = pv[which##_end].x - pv[which##_beg].x; \
- which##_slope = (which##_dx << 8) / which##_dy; \
- } while(0)
-
-void polyfill_flat(struct pvertex *pv, int nverts)
+void polyfill_tex_wire(struct pvertex *verts, int nverts)
{
- int i, sline, x, slen, top = 0;
- int left_beg, left_end, right_beg, right_end;
- int32_t left_dy, left_dx, right_dy, right_dx;
- int32_t left_slope, right_slope;
- int32_t left_x, right_x, y;
- uint16_t color = ((pv->r << 8) & 0xf800) | ((pv->g << 3) & 0x7e0) |
- ((pv->b >> 3) & 0x1f);
- uint16_t *pixptr;
-
- /* find topmost */
- for(i=1; i<nverts; i++) {
- if(pv[i].y < pv[top].y) {
- top = i;
- }
- }
- left_beg = right_beg = top;
- left_end = PREVIDX(left_beg);
- right_end = NEXTIDX(right_beg);
-
- if((left_dy = pv[left_end].y - pv[left_beg].y)) {
- CALC_EDGE(left);
- }
-
- if((right_dy = pv[right_end].y - pv[right_beg].y)) {
- CALC_EDGE(right);
- }
-
- y = pv[top].y;
- sline = pv[top].y >> 8;
-
- for(;;) {
- if(y >= pv[left_end].y) {
- while(y >= pv[left_end].y) {
- left_beg = left_end;
- if(left_beg == right_beg) return;
- left_end = PREVIDX(left_end);
- }
-
- left_dy = pv[left_end].y - pv[left_beg].y;
- CALC_EDGE(left);
- }
-
- if(y >= pv[right_end].y) {
- while(y >= pv[right_end].y) {
- right_beg = right_end;
- if(left_beg == right_beg) return;
- right_end = NEXTIDX(right_end);
- }
+ polyfill_wire(verts, nverts); /* TODO */
+}
- right_dy = pv[right_end].y - pv[right_beg].y;
- CALC_EDGE(right);
- }
+void polyfill_blend_wire(struct pvertex *verts, int nverts)
+{
+ polyfill_wire(verts, nverts); /* TODO */
+}
- x = left_x >> 8;
- slen = (right_x >> 8) - (left_x >> 8);
+void polyfill_blend_tex_wire(struct pvertex *verts, int nverts)
+{
+ polyfill_wire(verts, nverts); /* TODO */
+}
- pixptr = pimg_fb.pixels + sline * pimg_fb.width + x;
- for(i=0; i<slen; i++) {
- *pixptr++ += 15;
- }
+#define NEXTIDX(x) (((x) - 1 + nverts) % nverts)
+#define PREVIDX(x) (((x) + 1) % nverts)
- ++sline;
- y += 256;
- left_x += left_slope;
- right_x += right_slope;
- }
-}
+/* 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
+#undef BLEND
+#include "polytmpl.h"
+#undef POLYFILL
+#undef SCANEDGE
+
+#define POLYFILL polyfill_gouraud
+#define SCANEDGE scanedge_gouraud
+#define GOURAUD
+#undef TEXMAP
+#undef BLEND
+#include "polytmpl.h"
+#undef POLYFILL
+#undef SCANEDGE
+
+#define POLYFILL polyfill_tex_flat
+#define SCANEDGE scanedge_tex_flat
+#undef GOURAUD
+#define TEXMAP
+#undef BLEND
+#include "polytmpl.h"
+#undef POLYFILL
+#undef SCANEDGE
+
+#define POLYFILL polyfill_tex_gouraud
+#define SCANEDGE scanedge_tex_gouraud
+#define GOURAUD
+#define TEXMAP
+#undef BLEND
+#include "polytmpl.h"
+#undef POLYFILL
+#undef SCANEDGE
+
+#define POLYFILL polyfill_blend_flat
+#define SCANEDGE scanedge_blend_flat
+#undef GOURAUD
+#undef TEXMAP
+#define BLEND
+#include "polytmpl.h"
+#undef POLYFILL
+#undef SCANEDGE
+
+#define POLYFILL polyfill_blend_gouraud
+#define SCANEDGE scanedge_blend_gouraud
+#define GOURAUD
+#undef TEXMAP
+#define BLEND
+#include "polytmpl.h"
+#undef POLYFILL
+#undef SCANEDGE
+
+#define POLYFILL polyfill_blend_tex_flat
+#define SCANEDGE scanedge_blend_tex_flat
+#undef GOURAUD
+#define TEXMAP
+#define BLEND
+#include "polytmpl.h"
+#undef POLYFILL
+#undef SCANEDGE
+
+#define POLYFILL polyfill_blend_tex_gouraud
+#define SCANEDGE scanedge_blend_tex_gouraud
+#define GOURAUD
+#define TEXMAP
+#define BLEND
+#include "polytmpl.h"
+#undef POLYFILL
+#undef SCANEDGE
projects / dosdemo / blobdiff