X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?p=dosdemo;a=blobdiff_plain;f=src%2F3dgfx%2Fpolytmpl.h;fp=src%2F3dgfx%2Fpolytmpl.h;h=2072e2b5f19e01b4279084b83f2278e847f3f7b5;hp=0000000000000000000000000000000000000000;hb=57bd2dc519c47f434e3e5acf998fb9c72448cbce;hpb=d956a9d9273eebfacfda58cb3bafff017269d5dc

diff --git a/src/3dgfx/polytmpl.h b/src/3dgfx/polytmpl.h
new file mode 100644
index 0000000..2072e2b
--- /dev/null
+++ b/src/3dgfx/polytmpl.h
@@ -0,0 +1,363 @@
+static uint32_t SCANEDGE(struct pvertex *v0, struct pvertex *v1, struct pvertex *edge)
+{
+	int i;
+	int32_t x, dx, dy, slope;
+#ifdef GOURAUD
+	int r, g, b, dr, dg, db;
+	int32_t rslope, gslope, bslope;
+#ifdef BLEND_ALPHA
+	int32_t a, da, aslope;
+#endif
+#endif	/* GOURAUD */
+#ifdef TEXMAP
+	int32_t u, v, du, dv, uslope, vslope;
+#endif
+	int32_t start_idx, end_idx;
+
+	if(v0->y > v1->y) {
+		struct pvertex *tmp = v0;
+		v0 = v1;
+		v1 = tmp;
+	}
+
+	x = v0->x;
+	dy = v1->y - v0->y;
+	dx = v1->x - v0->x;
+	slope = (dx << 8) / dy;
+#ifdef GOURAUD
+	r = (v0->r << COLOR_SHIFT);
+	g = (v0->g << COLOR_SHIFT);
+	b = (v0->b << COLOR_SHIFT);
+	dr = (v1->r << COLOR_SHIFT) - r;
+	dg = (v1->g << COLOR_SHIFT) - g;
+	db = (v1->b << COLOR_SHIFT) - b;
+	rslope = (dr << 8) / dy;
+	gslope = (dg << 8) / dy;
+	bslope = (db << 8) / dy;
+#ifdef BLEND_ALPHA
+	a = (v0->a << COLOR_SHIFT);
+	da = (v1->a << COLOR_SHIFT) - a;
+	aslope = (da << 8) / dy;
+#endif	/* BLEND_ALPHA */
+#endif	/* GOURAUD */
+#ifdef TEXMAP
+	u = v0->u;
+	v = v0->v;
+	du = v1->u - v0->u;
+	dv = v1->v - v0->v;
+	uslope = (du << 8) / dy;
+	vslope = (dv << 8) / dy;
+#endif
+
+	start_idx = v0->y >> 8;
+	end_idx = v1->y >> 8;
+
+	for(i=start_idx; i<end_idx; i++) {
+		CHECKEDGE(i);
+		edge[i].x = x;
+		x += slope;
+#ifdef GOURAUD
+		/* we'll store the color in the edge tables with COLOR_SHIFT extra bits of precision */
+		CHECKEDGE(i);
+		edge[i].r = r;
+		edge[i].g = g;
+		edge[i].b = b;
+		r += rslope;
+		g += gslope;
+		b += bslope;
+#ifdef BLEND_ALPHA
+		CHECKEDGE(i);
+		edge[i].a = a;
+		a += aslope;
+#endif
+#endif	/* GOURAUD */
+#ifdef TEXMAP
+		CHECKEDGE(i);
+		edge[i].u = u;
+		edge[i].v = v;
+		u += uslope;
+		v += vslope;
+#endif
+	}
+
+	return (uint32_t)start_idx | ((uint32_t)(end_idx - 1) << 16);
+}
+
+void POLYFILL(struct pvertex *pv, int nverts)
+{
+	int i, winding;
+	int topidx = 0, botidx = 0, sltop = pfill_fb.height, slbot = 0;
+	g3d_pixel color;
+	/* the following variables are used for interpolating horizontally accros scanlines */
+#if defined(GOURAUD) || defined(TEXMAP)
+	int mid;
+	int32_t dx, tmp;
+#else
+	/* flat version, just pack the color now */
+	color = G3D_PACK_RGB(pv[0].r, pv[0].g, pv[0].b);
+#endif
+#ifdef GOURAUD
+	int32_t r, g, b, dr, dg, db, rslope, gslope, bslope;
+#ifdef BLEND_ALPHA
+	int32_t a, da, aslope;
+#endif
+#endif
+#ifdef TEXMAP
+	int32_t u, v, du, dv, uslope, vslope;
+#endif
+
+	for(i=1; i<nverts; i++) {
+		if(pv[i].y < pv[topidx].y) topidx = i;
+		if(pv[i].y > pv[botidx].y) botidx = i;
+	}
+
+	winding = 0;
+	for(i=0; i<nverts; i++) {
+		int next = NEXTIDX(i);
+		winding += ((pv[next].x - pv[i].x) >> 4) * ((pv[next].y + pv[i].y) >> 4);
+	}
+
+	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 i0, i1;
+				int idx = y0 >> 8;
+				if(pv[i].x < pv[next].x) {
+					i0 = i;
+					i1 = next;
+				} else {
+					i0 = next;
+					i1 = i;
+				}
+				CHECKEDGE(idx);
+				left[idx].x = pv[i0].x;
+				right[idx].x = pv[i1].x;
+#ifdef GOURAUD
+				left[idx].r = pv[i0].r << COLOR_SHIFT;
+				left[idx].g = pv[i0].g << COLOR_SHIFT;
+				left[idx].b = pv[i0].b << COLOR_SHIFT;
+				right[idx].r = pv[i1].r << COLOR_SHIFT;
+				right[idx].g = pv[i1].g << COLOR_SHIFT;
+				right[idx].b = pv[i1].b << COLOR_SHIFT;
+#ifdef BLEND_ALPHA
+				left[idx].a = pv[i0].a << COLOR_SHIFT;
+				right[idx].a = pv[i1].a << COLOR_SHIFT;
+#endif	/* BLEND_ALPHA */
+#endif
+#ifdef TEXMAP
+				left[idx].u = pv[i0].u;
+				left[idx].v = pv[i0].v;
+				right[idx].u = pv[i1].u;
+				right[idx].v = pv[i1].v;
+#endif
+				CHECKEDGE(idx);
+				if(idx > slbot) slbot = idx;
+				if(idx < sltop) sltop = idx;
+			/*}*/
+		} else {
+			struct pvertex *edge;
+			uint32_t res, tmp;
+
+			if(winding < 0) {
+				/* clockwise */
+				edge = y0 > y1 ? left : right;
+			} else {
+				/* counter-clockwise */
+				edge = y0 > y1 ? right : left;
+			}
+			res = SCANEDGE(pv + i, pv + next, edge);
+			tmp = (res >> 16) & 0xffff;
+			if(tmp > slbot) slbot = tmp;
+			if((tmp = res & 0xffff) < sltop) {
+				sltop = tmp;
+			}
+		}
+	}
+
+	/* calculate the slopes of all attributes across the largest span out
+	 * of the three: middle, top, or bottom.
+	 */
+#ifndef HIGH_QUALITY
+#if defined(GOURAUD) || defined(TEXMAP)
+	mid = (sltop + slbot) >> 1;
+	CHECKEDGE(sltop);
+	CHECKEDGE(slbot);
+	CHECKEDGE(mid);
+	dx = right[mid].x - left[mid].x;
+	if((tmp = right[sltop].x - left[sltop].x) > dx) {
+		dx = tmp;
+		mid = sltop;
+	}
+	if((tmp = right[slbot].x - left[slbot].x) > dx) {
+		dx = tmp;
+		mid = slbot;
+	}
+	if(!dx) dx = 256;	/* avoid division by zero */
+#endif
+	CHECKEDGE(idx);
+#ifdef GOURAUD
+	dr = right[mid].r - left[mid].r;
+	dg = right[mid].g - left[mid].g;
+	db = right[mid].b - left[mid].b;
+	rslope = (dr << 8) / dx;
+	gslope = (dg << 8) / dx;
+	bslope = (db << 8) / dx;
+#ifdef BLEND_ALPHA
+	da = right[mid].a - left[mid].a;
+	aslope = (da << 8) / dx;
+#endif	/* BLEND_ALPHA */
+#endif
+#ifdef TEXMAP
+	du = right[mid].u - left[mid].u;
+	dv = right[mid].v - left[mid].v;
+	uslope = (du << 8) / dx;
+	vslope = (dv << 8) / dx;
+#endif
+#endif	/* !defined(HIGH_QUALITY) */
+
+	/* for each scanline ... */
+	for(i=sltop; i<=slbot; i++) {
+		g3d_pixel *pixptr;
+		int32_t x;
+
+		CHECKEDGE(i);
+		x = left[i].x;
+		pixptr = pfill_fb.pixels + i * pfill_fb.width + (x >> 8);
+
+#ifdef GOURAUD
+		r = left[i].r;
+		g = left[i].g;
+		b = left[i].b;
+#ifdef BLEND_ALPHA
+		a = left[i].a;
+#endif	/* BLEND_ALPHA */
+#endif
+#ifdef TEXMAP
+		u = left[i].u;
+		v = left[i].v;
+#endif
+		CHECKEDGE(i);
+
+#if defined(HIGH_QUALITY) && (defined(GOURAUD) || defined(TEXMAP))
+		if(!(dx = right[i].x - left[i].x)) dx = 256;
+
+		CHECKEDGE(i);
+#ifdef GOURAUD
+		dr = right[i].r - left[i].r;
+		dg = right[i].g - left[i].g;
+		db = right[i].b - left[i].b;
+		rslope = (dr << 8) / dx;
+		gslope = (dg << 8) / dx;
+		bslope = (db << 8) / dx;
+#ifdef BLEND_ALPHA
+		da = right[i].a - left[i].a;
+		aslope = (da << 8) / dx;
+#endif	/* BLEND_ALPHA */
+#endif	/* GOURAUD */
+#ifdef TEXMAP
+		du = right[i].u - left[i].u;
+		dv = right[i].v - left[i].v;
+		uslope = (du << 8) / dx;
+		vslope = (dv << 8) / dx;
+#endif
+#endif	/* HIGH_QUALITY */
+		CHECKEDGE(i);
+
+		/* go across the scanline interpolating if necessary */
+		while(x <= right[i].x) {
+#if defined(GOURAUD) || defined(TEXMAP) || defined(BLEND_ALPHA) || defined(BLEND_ADD)
+			int cr, cg, cb;
+#endif
+#if defined(BLEND_ALPHA) || defined(BLEND_ADD)
+			g3d_pixel fbcol;
+#endif
+#ifdef BLEND_ALPHA
+			int alpha, inv_alpha;
+#endif
+#ifdef GOURAUD
+			/* we upped the color precision to while interpolating the
+			 * edges, now drop the extra bits before packing
+			 */
+			cr = r < 0 ? 0 : (r >> COLOR_SHIFT);
+			cg = g < 0 ? 0 : (g >> COLOR_SHIFT);
+			cb = b < 0 ? 0 : (b >> COLOR_SHIFT);
+			r += rslope;
+			g += gslope;
+			b += bslope;
+#ifdef BLEND_ALPHA
+			a += aslope;
+#else
+			if(cr > 255) cr = 255;
+			if(cg > 255) cg = 255;
+			if(cb > 255) cb = 255;
+#endif	/* BLEND_ALPHA */
+#endif	/* GOURAUD */
+#ifdef TEXMAP
+			{
+				int tx = (u >> (16 - pfill_tex.xshift)) & pfill_tex.xmask;
+				int ty = (v >> (16 - pfill_tex.yshift)) & pfill_tex.ymask;
+				g3d_pixel texel = pfill_tex.pixels[(ty << pfill_tex.xshift) + tx];
+#ifdef 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
+				 */
+				cr = (cr * G3D_UNPACK_R(texel)) >> 8;
+				cg = (cg * G3D_UNPACK_G(texel)) >> 8;
+				cb = (cb * G3D_UNPACK_B(texel)) >> 8;
+#else
+				cr = G3D_UNPACK_R(texel);
+				cg = G3D_UNPACK_G(texel);
+				cb = G3D_UNPACK_B(texel);
+#endif
+			}
+			u += uslope;
+			v += vslope;
+#endif
+
+#if defined(BLEND_ALPHA) || defined(BLEND_ADD)
+#if !defined(GOURAUD) && !defined(TEXMAP)
+			/* flat version: cr,cg,cb are uninitialized so far */
+			cr = pv[0].r;
+			cg = pv[0].g;
+			cb = pv[0].b;
+#endif
+			fbcol = *pixptr;
+
+#ifdef BLEND_ALPHA
+#ifdef GOURAUD
+			alpha = a >> COLOR_SHIFT;
+#else
+			alpha = pv[0].a;
+#endif
+			inv_alpha = 255 - alpha;
+			cr = (cr * alpha + G3D_UNPACK_R(fbcol) * inv_alpha) >> 8;
+			cg = (cg * alpha + G3D_UNPACK_G(fbcol) * inv_alpha) >> 8;
+			cb = (cb * alpha + G3D_UNPACK_B(fbcol) * inv_alpha) >> 8;
+#else	/* !BLEND_ALPHA (so BLEND_ADD) */
+			cr += G3D_UNPACK_R(fbcol);
+			cg += G3D_UNPACK_R(fbcol);
+			cb += G3D_UNPACK_R(fbcol);
+#endif
+			if(cr > 255) cr = 255;
+			if(cg > 255) cg = 255;
+			if(cb > 255) cb = 255;
+#endif	/* BLEND(ALPHA|ADD) */
+
+#if defined(GOURAUD) || defined(TEXMAP) || defined(BLEND_ALPHA) || defined(BLEND_ADD)
+			color = G3D_PACK_RGB(cr, cg, cb);
+#endif
+
+#ifdef DEBUG_OVERDRAW
+			*pixptr++ += DEBUG_OVERDRAW;
+#else
+			*pixptr++ = color;
+#endif
+			x += 256;
+		}
+	}
+}
+