X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?a=blobdiff_plain;f=src%2Fxgl.c;h=7d22b2bc4e65cab65946a9cab5ed721effc6ec38;hb=ee0d92a6e621e6a8135b16914a09def52bd70a4b;hp=48db2200a89b4bd1ebbcd5e4a91db0ee258d1256;hpb=ff8e2d7dab918d2e303f941fad00dee6bb80544e;p=gbajam22

diff --git a/src/xgl.c b/src/xgl.c
index 48db220..7d22b2b 100644
--- a/src/xgl.c
+++ b/src/xgl.c
@@ -20,6 +20,7 @@ along with this program.  If not, see <https://www.gnu.org/licenses/>.
 #include "xgl.h"
 #include "polyfill.h"
 #include "debug.h"
+#include "util.h"
 
 #define MAT_STACK_SIZE	4
 
@@ -29,6 +30,8 @@ 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);
 
 
@@ -116,8 +119,13 @@ void xgl_mult_matrix(const int32_t *m2)
 	}
 }
 
+#if 0
 #define XSIN(x)		(int32_t)(sin(x / 65536.0f) * 65536.0f)
 #define XCOS(x)		(int32_t)(cos(x / 65536.0f) * 65536.0f)
+#else
+#define XSIN(x)		SIN(((x) << 8) / (X_2PI >> 8))
+#define XCOS(x)		COS(((x) << 8) / (X_2PI >> 8))
+#endif
 
 void xgl_translate(int32_t x, int32_t y, int32_t z)
 {
@@ -174,14 +182,19 @@ void xgl_scale(int32_t x, int32_t y, int32_t z)
 	xgl_mult_matrix(m);
 }
 
-static void xform(struct xvertex *out, const struct xvertex *in, const int32_t *m)
+void xgl_index(int cidx)
+{
+	cur_cidx = cidx;
+}
+
+static inline 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];
 	out->y = XMUL(m[1], in->x) + XMUL(m[5], in->y) + XMUL(m[9], in->z) + m[13];
 	out->z = XMUL(m[2], in->x) + XMUL(m[6], in->y) + XMUL(m[10], in->z) + m[14];
 }
 
-static void xform_norm(struct xvertex *out, const struct xvertex *in, const int32_t *m)
+static inline void xform_norm(struct xvertex *out, const struct xvertex *in, const int32_t *m)
 {
 	out->nx = XMUL(m[0], in->nx) + XMUL(m[4], in->ny) + XMUL(m[8], in->nz);
 	out->ny = XMUL(m[1], in->nx) + XMUL(m[5], in->ny) + XMUL(m[9], in->nz);
@@ -191,12 +204,13 @@ 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
 
+ARM_IWRAM
 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 +220,11 @@ 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 +234,24 @@ 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 +303,7 @@ 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 { \
@@ -308,6 +318,7 @@ void xgl_xyzzy(void)
 		(res)->lit = (v0)->lit + (((v1)->lit - (v0)->lit) >> 8) * (t); \
 	} while(0)
 
+ARM_IWRAM
 static int clip_edge_near(struct xvertex *poly, int *vnumptr, struct xvertex *v0, struct xvertex *v1)
 {
 	int vnum = *vnumptr;
@@ -353,6 +364,7 @@ static int clip_edge_near(struct xvertex *poly, int *vnumptr, struct xvertex *v0
 }
 
 /* special case near-plane clipper */
+ARM_IWRAM
 int xgl_clip_near(struct xvertex *vout, int *voutnum, struct xvertex *vin, int vnum)
 {
 	int i, nextidx, res;