fixed clipping, emuprint for mgba, foo

[gbajam22] / src / xgl.c

diff --git a/src/xgl.c b/src/xgl.c
index 8f59d90..3efae76 100644 (file)
--- a/src/xgl.c
+++ b/src/xgl.c
@@ -116,6 +116,7 @@ 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)
 
@@ -191,7 +192,7 @@ 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 0x40000
+#define NEAR_Z 0x18000
 
 void xgl_draw(int prim, const struct xvertex *varr, int vcount)
 {
@@ -211,9 +212,6 @@ void xgl_draw(int prim, const struct xvertex *varr, int vcount)
                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];
@@ -223,19 +221,18 @@ 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<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 = (((xvclip[i].x + 0x100) >> 1) * vp[2]) + (vp[0] << 8);
                        pv[i].y = (((0x100 - xvclip[i].y) >> 1) * vp[3]) + (vp[1] << 8);
@@ -293,14 +290,13 @@ void xgl_xyzzy(void)
        mat[mtop][12] = mat[mtop][13] = 0;
 }
 
-/* 24.8 */
 #define ISECT_NEAR(v0, v1)     ((((v0)->z - NEAR_Z) << 8) / ((v0)->z - (v1)->z))
 
 #define LERP_VATTR(res, v0, v1, t) \
        do { \
-               (res)->x = (v0)->x + (((v1)->x - (v0)->x) * (t) >> 8);  \
-               (res)->y = (v0)->y + (((v1)->y - (v0)->y) * (t) >> 8);  \
-               (res)->z = (v0)->z + (((v1)->z - (v0)->nx) >> 8) * (t); \
+               (res)->x = (v0)->x + (((v1)->x - (v0)->x) >> 8) * (t);  \
+               (res)->y = (v0)->y + (((v1)->y - (v0)->y) >> 8) * (t);  \
+               (res)->z = (v0)->z + (((v1)->z - (v0)->z) >> 8) * (t);  \
                (res)->nx = (v0)->nx + (((v1)->nx - (v0)->nx) >> 8) * (t);      \
                (res)->ny = (v0)->ny + (((v1)->ny - (v0)->ny) >> 8) * (t);      \
                (res)->nz = (v0)->nz + (((v1)->nz - (v0)->nz) >> 8) * (t);      \