X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?a=blobdiff_plain;f=src%2Fxgl.c;h=368c498fcd500b9b8e3fa3e70f0d596c486688a5;hb=c52a5978823a77da3570cb73b985b928bb8358d9;hp=48db2200a89b4bd1ebbcd5e4a91db0ee258d1256;hpb=ff8e2d7dab918d2e303f941fad00dee6bb80544e;p=gbajam22

diff --git a/src/xgl.c b/src/xgl.c
index 48db220..368c498 100644
--- a/src/xgl.c
+++ b/src/xgl.c
@@ -29,6 +29,8 @@ static int mtop;
 static unsigned int opt;
 static int32_t ldir[3];
 
+static int cur_cidx;
+
 static void draw_ptlines(int prim, const struct xvertex *varr, int vcount);
 
 
@@ -116,6 +118,7 @@ void xgl_mult_matrix(const int32_t *m2)
 	}
 }
 
+/* XXX TODO XXX */
 #define XSIN(x)		(int32_t)(sin(x / 65536.0f) * 65536.0f)
 #define XCOS(x)		(int32_t)(cos(x / 65536.0f) * 65536.0f)
 
@@ -174,6 +177,11 @@ void xgl_scale(int32_t x, int32_t y, int32_t z)
 	xgl_mult_matrix(m);
 }
 
+void xgl_index(int cidx)
+{
+	cur_cidx = cidx;
+}
+
 static void xform(struct xvertex *out, const struct xvertex *in, const int32_t *m)
 {
 	out->x = XMUL(m[0], in->x) + XMUL(m[4], in->y) + XMUL(m[8], in->z) + m[12];
@@ -191,12 +199,12 @@ static void xform_norm(struct xvertex *out, const struct xvertex *in, const int3
 /* d = 1.0 / tan(fov/2) */
 #define PROJ_D	0x20000
 /* near Z = 0.5 */
-#define NEAR_Z	0x10000
+#define NEAR_Z	0x18000
 
 void xgl_draw(int prim, const struct xvertex *varr, int vcount)
 {
-	int i, cidx;
-	struct xvertex xv[4];
+	int i, cidx, clipnum;
+	struct xvertex xv[4], xvclip[8];
 	struct pvertex pv[4];
 	int32_t ndotl;
 
@@ -206,14 +214,11 @@ void xgl_draw(int prim, const struct xvertex *varr, int vcount)
 	}
 
 	while(vcount >= prim) {
-		cidx = 0xff;//varr->cidx;
+		cidx = cur_cidx;//varr->cidx;
 
 		xform(xv, varr, mat[mtop]);
 		xform_norm(xv, varr, mat[mtop]);
 
-		/* backfacing check */
-		if(xv->nz > 0) goto skip_poly;
-
 		/*
 		if(opt & XGL_LIGHTING) {
 			ndotl = (xv->nx >> 8) * ldir[0] + (xv->ny >> 8) * ldir[1] + (xv->nz >> 8) * ldir[2];
@@ -223,25 +228,24 @@ void xgl_draw(int prim, const struct xvertex *varr, int vcount)
 		}
 		*/
 
-		for(i=0; i<prim; i++) {
-			if(i > 0) {
-				xform(xv + i, varr + i, mat[mtop]);
-			}
-			xv[i].x = (xv[i].x << 1) / (xv[i].z >> 8);	/* assume aspect: ~2 */
-			xv[i].y = (xv[i].y << 2) / (xv[i].z >> 8);	/* the shift is * PROJ_D */
-			/* transform result is 24.8 */
+		/* transform the rest of the vertices to view space */
+		for(i=1; i<prim; i++) {
+			xform(xv + i, varr + i, mat[mtop]);
 		}
 
 		/* clip against near plane */
+		xgl_clip_near(xvclip, &clipnum, xv, prim);
 
-
-		for(i=0; i<prim; i++) {
+		for(i=0; i<clipnum; i++) {
+			xvclip[i].x = (xvclip[i].x << 1) / (xvclip[i].z >> 8);	/* assume aspect: ~2 */
+			xvclip[i].y = (xvclip[i].y << 2) / (xvclip[i].z >> 8);	/* the shift is * PROJ_D */
+			/* transform result is 24.8 */
 			/* viewport */
-			pv[i].x = (((xv[i].x + 0x100) >> 1) * vp[2]) + (vp[0] << 8);
-			pv[i].y = (((0x100 - xv[i].y) >> 1) * vp[3]) + (vp[1] << 8);
+			pv[i].x = (((xvclip[i].x + 0x100) >> 1) * vp[2]) + (vp[0] << 8);
+			pv[i].y = (((0x100 - xvclip[i].y) >> 1) * vp[3]) + (vp[1] << 8);
 		}
 
-		polyfill_flat(pv, prim, cidx);
+		polyfill_flat(pv, clipnum, cidx);
 skip_poly:
 		varr += prim;
 		vcount -= prim;
@@ -293,7 +297,7 @@ void xgl_xyzzy(void)
 	mat[mtop][12] = mat[mtop][13] = 0;
 }
 
-#define ISECT_NEAR(v0, v1)	((((v0)->z - NEAR_Z) << 8) / (((v0)->z - (v1)->z) >> 8))
+#define ISECT_NEAR(v0, v1)	((((v0)->z - NEAR_Z) << 8) / ((v0)->z - (v1)->z))
 
 #define LERP_VATTR(res, v0, v1, t) \
 	do { \