--- /dev/null
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <assert.h>
+#if defined(__WATCOMC__) || defined(_WIN32) || 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 3-4: blend mode: 00-none 01-alpha 10-additive 11-reserved
+ */
+void (*fillfunc[])(struct pvertex*, int) = {
+ polyfill_wire,
+ polyfill_flat,
+ polyfill_gouraud,
+ 0,
+ polyfill_tex_wire,
+ polyfill_tex_flat,
+ polyfill_tex_gouraud,
+ 0,
+ polyfill_alpha_wire,
+ polyfill_alpha_flat,
+ polyfill_alpha_gouraud,
+ 0,
+ polyfill_alpha_tex_wire,
+ polyfill_alpha_tex_flat,
+ polyfill_alpha_tex_gouraud,
+ 0,
+ polyfill_add_wire,
+ polyfill_add_flat,
+ polyfill_add_gouraud,
+ 0,
+ polyfill_add_tex_wire,
+ polyfill_add_tex_flat,
+ polyfill_add_tex_gouraud,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0
+};
+
+struct pimage pfill_fb, pfill_tex;
+
+#define EDGEPAD 8
+static struct pvertex *edgebuf, *left, *right;
+static int edgebuf_size;
+static int fbheight;
+
+/*
+#define CHECKEDGE(x) \
+ do { \
+ assert(x >= 0); \
+ assert(x < fbheight); \
+ } while(0)
+*/
+#define CHECKEDGE(x)
+
+
+void polyfill_fbheight(int height)
+{
+ void *tmp;
+ int newsz = (height * 2 + EDGEPAD * 3) * sizeof *edgebuf;
+
+ if(newsz > edgebuf_size) {
+ free(edgebuf);
+ if(!(edgebuf = malloc(newsz))) {
+ fprintf(stderr, "failed to allocate edge table buffer (%d bytes)\n", newsz);
+ abort();
+ }
+ edgebuf_size = newsz;
+
+ left = edgebuf + EDGEPAD;
+ right = edgebuf + height + EDGEPAD * 2;
+
+#ifndef NDEBUG
+ memset(edgebuf, 0xaa, EDGEPAD * sizeof *edgebuf);
+ memset(edgebuf + height + EDGEPAD, 0xaa, EDGEPAD * sizeof *edgebuf);
+ memset(edgebuf + height * 2 + EDGEPAD * 2, 0xaa, EDGEPAD * sizeof *edgebuf);
+#endif
+ }
+
+ fbheight = height;
+}
+
+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_alpha_wire(struct pvertex *verts, int nverts)
+{
+ polyfill_wire(verts, nverts); /* TODO */
+}
+
+void polyfill_alpha_tex_wire(struct pvertex *verts, int nverts)
+{
+ polyfill_wire(verts, nverts); /* TODO */
+}
+
+void polyfill_add_wire(struct pvertex *verts, int nverts)
+{
+ polyfill_wire(verts, nverts); /* TODO */
+}
+
+void polyfill_add_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_ALPHA
+#undef BLEND_ADD
+#include "polytmpl.h"
+#undef POLYFILL
+#undef SCANEDGE
+
+#define POLYFILL polyfill_gouraud
+#define SCANEDGE scanedge_gouraud
+#define GOURAUD
+#undef TEXMAP
+#undef BLEND_ALPHA
+#undef BLEND_ADD
+#include "polytmpl.h"
+#undef POLYFILL
+#undef SCANEDGE
+
+#define POLYFILL polyfill_tex_flat
+#define SCANEDGE scanedge_tex_flat
+#undef GOURAUD
+#define TEXMAP
+#undef BLEND_ALPHA
+#undef BLEND_ADD
+#include "polytmpl.h"
+#undef POLYFILL
+#undef SCANEDGE
+
+#define POLYFILL polyfill_tex_gouraud
+#define SCANEDGE scanedge_tex_gouraud
+#define GOURAUD
+#define TEXMAP
+#undef BLEND_ALPHA
+#undef BLEND_ADD
+#include "polytmpl.h"
+#undef POLYFILL
+#undef SCANEDGE
+
+#define POLYFILL polyfill_alpha_flat
+#define SCANEDGE scanedge_alpha_flat
+#undef GOURAUD
+#undef TEXMAP
+#define BLEND_ALPHA
+#undef BLEND_ADD
+#include "polytmpl.h"
+#undef POLYFILL
+#undef SCANEDGE
+
+#define POLYFILL polyfill_alpha_gouraud
+#define SCANEDGE scanedge_alpha_gouraud
+#define GOURAUD
+#undef TEXMAP
+#define BLEND_ALPHA
+#undef BLEND_ADD
+#include "polytmpl.h"
+#undef POLYFILL
+#undef SCANEDGE
+
+#define POLYFILL polyfill_alpha_tex_flat
+#define SCANEDGE scanedge_alpha_tex_flat
+#undef GOURAUD
+#define TEXMAP
+#define BLEND_ALPHA
+#undef BLEND_ADD
+#include "polytmpl.h"
+#undef POLYFILL
+#undef SCANEDGE
+
+#define POLYFILL polyfill_alpha_tex_gouraud
+#define SCANEDGE scanedge_alpha_tex_gouraud
+#define GOURAUD
+#define TEXMAP
+#define BLEND_ALPHA
+#undef BLEND_ADD
+#include "polytmpl.h"
+#undef POLYFILL
+#undef SCANEDGE
+
+#define POLYFILL polyfill_add_flat
+#define SCANEDGE scanedge_add_flat
+#undef GOURAUD
+#undef TEXMAP
+#undef BLEND_ALPHA
+#define BLEND_ADD
+#include "polytmpl.h"
+#undef POLYFILL
+#undef SCANEDGE
+
+#define POLYFILL polyfill_add_gouraud
+#define SCANEDGE scanedge_add_gouraud
+#define GOURAUD
+#undef TEXMAP
+#undef BLEND_ALPHA
+#define BLEND_ADD
+#include "polytmpl.h"
+#undef POLYFILL
+#undef SCANEDGE
+
+#define POLYFILL polyfill_add_tex_flat
+#define SCANEDGE scanedge_add_tex_flat
+#undef GOURAUD
+#define TEXMAP
+#undef BLEND_ALPHA
+#define BLEND_ADD
+#include "polytmpl.h"
+#undef POLYFILL
+#undef SCANEDGE
+
+#define POLYFILL polyfill_add_tex_gouraud
+#define SCANEDGE scanedge_add_tex_gouraud
+#define GOURAUD
+#define TEXMAP
+#undef BLEND_ALPHA
+#define BLEND_ADD
+#include "polytmpl.h"
+#undef POLYFILL
+#undef SCANEDGE
projects / dosdemo / blobdiff