moved over the polyfiller code and implemented blending

[bootcensus] / src / census / polyfill.c

diff --git a/src/census/polyfill.c b/src/census/polyfill.c
new file mode 100644 (file)
index 0000000..3f94e25
--- /dev/null
+++ b/src/census/polyfill.c
@@ -0,0 +1,179 @@
+#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"
+
+#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,
+       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 pfill_fb, pfill_tex;
+
+void polyfill(int mode, struct pvertex *verts, int nverts)
+{
+#ifndef NDEBUG
+       if(!fillfunc[mode]) {
+               fprintf(stderr, "polyfill mode %d not implemented\n", mode);
+               abort();
+       }
+#endif
+
+       fillfunc[mode](verts, nverts);
+}
+
+void polyfill_wire(struct pvertex *verts, int nverts)
+{
+       int i, x0, y0, x1, y1;
+       struct pvertex *v = verts;
+       unsigned short color = ((v->r << 8) & 0xf800) |
+               ((v->g << 3) & 0x7e0) | ((v->b >> 3) & 0x1f);
+
+       for(i=0; i<nverts - 1; i++) {
+               x0 = v->x >> 8;
+               y0 = v->y >> 8;
+               ++v;
+               x1 = v->x >> 8;
+               y1 = v->y >> 8;
+               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, pfill_fb.width, pfill_fb.height)) {
+               draw_line(x1, y1, x0, y0, color);
+       }
+}
+
+void polyfill_tex_wire(struct pvertex *verts, int nverts)
+{
+       polyfill_wire(verts, nverts);   /* TODO */
+}
+
+void polyfill_blend_wire(struct pvertex *verts, int nverts)
+{
+       polyfill_wire(verts, nverts);   /* TODO */
+}
+
+void polyfill_blend_tex_wire(struct pvertex *verts, int nverts)
+{
+       polyfill_wire(verts, nverts);   /* TODO */
+}
+
+#define NEXTIDX(x) (((x) - 1 + nverts) % nverts)
+#define PREVIDX(x) (((x) + 1) % nverts)
+
+/* 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