delay backface culling till after near plane test

git-svn-id: svn://svn.icculus.org/twilight/trunk/darkplaces@10764 d7cf8633-e32d-0410-b094-e92efae38249

diff --git a/dpsoftrast.c b/dpsoftrast.c
index 684874c5a10c715fa577e40fbddcbcab03cd0c4c..bbb5efd9fac6ea6e5f49d8c53cefa1440cee899c 100644 (file)
--- a/dpsoftrast.c
+++ b/dpsoftrast.c
@@ -1113,7 +1113,7 @@ void DPSOFTRAST_Array_Copy(float *out4f, const float *in4f, int numitems)
 }
 
 #ifdef SSE2_PRESENT
-__m128 DPSOFTRAST_Draw_ProjectVertex(__m128 v)
+static __m128 DPSOFTRAST_Draw_ProjectVertex(__m128 v)
 {
        __m128 viewportcenter = _mm_load_ps(dpsoftrast.fb_viewportcenter), viewportscale = _mm_load_ps(dpsoftrast.fb_viewportscale);
        __m128 w = _mm_rcp_ss(_mm_shuffle_ps(v, v, _MM_SHUFFLE(2, 1, 0, 3)));
@@ -3415,6 +3415,7 @@ void DPSOFTRAST_Draw_ProcessTriangles(int firstvertex, int numtriangles, const i
        int cullface = dpsoftrast.user.cullface;
        int width = dpsoftrast.fb_width;
        int height = dpsoftrast.fb_height;
+       __m128i fbmax = _mm_sub_epi16(_mm_setr_epi16(width, height, width, height, width, height, width, height), _mm_set1_epi16(1));
        int i;
        int j;
        int k;
@@ -3430,7 +3431,6 @@ void DPSOFTRAST_Draw_ProcessTriangles(int firstvertex, int numtriangles, const i
        int startx;
        int endx;
        unsigned char mip[DPSOFTRAST_MAXTEXTUREUNITS];
-       __m128 triangleedge[2], triangleorigin, trianglenormal;
        __m128 mipedgescale;
        float clipdist[4];
        __m128 clipped[DPSOFTRAST_ARRAY_TOTAL][4];
@@ -3461,36 +3461,34 @@ void DPSOFTRAST_Draw_ProcessTriangles(int firstvertex, int numtriangles, const i
                        e[1] = i*3+1;
                        e[2] = i*3+2;
                }
-               triangleorigin = _mm_load_ps(&dpsoftrast.draw.post_array4f[DPSOFTRAST_ARRAY_POSITION][e[1]*4]);
-               triangleedge[0] = _mm_sub_ps(_mm_load_ps(&dpsoftrast.draw.post_array4f[DPSOFTRAST_ARRAY_POSITION][e[0]*4]), triangleorigin);
-               triangleedge[1] = _mm_sub_ps(_mm_load_ps(&dpsoftrast.draw.post_array4f[DPSOFTRAST_ARRAY_POSITION][e[2]*4]), triangleorigin);
-               // store normal in 2, 0, 1 order instead of 0, 1, 2 as it requires fewer shuffles and leaves z component accessible as scalar
-               trianglenormal = _mm_sub_ps(_mm_mul_ps(triangleedge[0], _mm_shuffle_ps(triangleedge[1], triangleedge[1], _MM_SHUFFLE(3, 0, 2, 1))),
-                                                                       _mm_mul_ps(_mm_shuffle_ps(triangleedge[0], triangleedge[0], _MM_SHUFFLE(3, 0, 2, 1)), triangleedge[1]));
-#if 0
-               trianglenormal[2] = triangleedge[0][0] * triangleedge[1][1] - triangleedge[0][1] * triangleedge[1][0];
-               trianglenormal[0] = triangleedge[0][1] * triangleedge[1][2] - triangleedge[0][2] * triangleedge[1][1];
-               trianglenormal[1] = triangleedge[0][2] * triangleedge[1][0] - triangleedge[0][0] * triangleedge[1][2];
-#endif
-               // apply current cullface mode (this culls many triangles)
-               switch(cullface)
-               {
-               case GL_BACK:
-                       if (_mm_ucomilt_ss(trianglenormal, _mm_setzero_ps()))
-                               continue;
-                       break;
-               case GL_FRONT:
-                       if (_mm_ucomigt_ss(trianglenormal, _mm_setzero_ps()))
-                               continue;
-                       break;
+
+#define SKIPBACKFACE { \
+                       __m128 triangleedge[2], triangleorigin, trianglenormal; \
+                       triangleorigin = _mm_load_ps(&dpsoftrast.draw.post_array4f[DPSOFTRAST_ARRAY_POSITION][e[1]*4]); \
+                       triangleedge[0] = _mm_sub_ps(_mm_load_ps(&dpsoftrast.draw.post_array4f[DPSOFTRAST_ARRAY_POSITION][e[0]*4]), triangleorigin); \
+                       triangleedge[1] = _mm_sub_ps(_mm_load_ps(&dpsoftrast.draw.post_array4f[DPSOFTRAST_ARRAY_POSITION][e[2]*4]), triangleorigin); \
+                       /* store normal in 2, 0, 1 order instead of 0, 1, 2 as it requires fewer shuffles and leaves z component accessible as scalar */ \
+                       trianglenormal = _mm_sub_ss(_mm_mul_ss(triangleedge[0], _mm_shuffle_ps(triangleedge[1], triangleedge[1], _MM_SHUFFLE(3, 0, 2, 1))), \
+                                                                               _mm_mul_ss(_mm_shuffle_ps(triangleedge[0], triangleedge[0], _MM_SHUFFLE(3, 0, 2, 1)), triangleedge[1])); \
+                       /* apply current cullface mode (this culls many triangles) */ \
+                       switch(cullface) \
+                       { \
+                       case GL_BACK: \
+                               if (_mm_ucomilt_ss(trianglenormal, _mm_setzero_ps())) \
+                                       continue; \
+                               break; \
+                       case GL_FRONT: \
+                               if (_mm_ucomigt_ss(trianglenormal, _mm_setzero_ps())) \
+                                       continue; \
+                               break; \
+                       } \
                }
-#if 0
-               trianglearea2 = trianglenormal[0] * trianglenormal[0] + trianglenormal[1] * trianglenormal[1] + trianglenormal[2] * trianglenormal[2];
-               // skip degenerate triangles, nothing good can come from them...
-               if (trianglearea2 == 0.0f)
-                       continue;
-#endif
-               
+                       //trianglenormal = _mm_sub_ps(_mm_mul_ps(triangleedge[0], _mm_shuffle_ps(triangleedge[1], triangleedge[1], _MM_SHUFFLE(3, 0, 2, 1))),
+                       //                                                _mm_mul_ps(_mm_shuffle_ps(triangleedge[0], triangleedge[0], _MM_SHUFFLE(3, 0, 2, 1)), triangleedge[1]));
+                       //trianglenormal[2] = triangleedge[0][0] * triangleedge[1][1] - triangleedge[0][1] * triangleedge[1][0];
+                       //trianglenormal[0] = triangleedge[0][1] * triangleedge[1][2] - triangleedge[0][2] * triangleedge[1][1];
+                       //trianglenormal[1] = triangleedge[0][2] * triangleedge[1][0] - triangleedge[0][0] * triangleedge[1][2];
+
                        // macros for clipping vertices
 #define CLIPPEDVERTEXLERP(k,p1,p2) { \
                        __m128 frac = _mm_set1_ps(clipdist[p1] / (clipdist[p1] - clipdist[p2]));\
@@ -3520,6 +3518,7 @@ void DPSOFTRAST_Draw_ProcessTriangles(int firstvertex, int numtriangles, const i
                clipdist[2] = dpsoftrast.draw.post_array4f[DPSOFTRAST_ARRAY_POSITION][e[2]*4+2] + 1.0f;
                if (clipdist[0] >= 0.0f)
                {
+                       SKIPBACKFACE;
                        if (clipdist[1] >= 0.0f)
                        {
                                CLIPPEDVERTEXCOPY(0,0);
@@ -3556,6 +3555,7 @@ void DPSOFTRAST_Draw_ProcessTriangles(int firstvertex, int numtriangles, const i
                }                       
                else if (clipdist[1] >= 0.0f)
                {
+                       SKIPBACKFACE;
                        CLIPPEDVERTEXLERP(0,0,1);
                        CLIPPEDVERTEXCOPY(1,1);
                        if (clipdist[2] >= 0.0f)
@@ -3572,25 +3572,25 @@ void DPSOFTRAST_Draw_ProcessTriangles(int firstvertex, int numtriangles, const i
                }
                else if (clipdist[2] >= 0.0f)
                {
+                       SKIPBACKFACE;
                        CLIPPEDVERTEXLERP(0,1,2);
                        CLIPPEDVERTEXCOPY(1,2);
                        CLIPPEDVERTEXLERP(2,2,0);
                        numpoints = 3;
                }
                else continue; // triangle is entirely behind nearpla
+
                {
                        // calculate integer y coords for triangle points
                        __m128i screeni = _mm_packs_epi32(_mm_cvttps_epi32(_mm_shuffle_ps(screen[0], screen[1], _MM_SHUFFLE(1, 0, 1, 0))),
-                                                                                 _mm_cvttps_epi32(_mm_shuffle_ps(screen[2], screen[3], _MM_SHUFFLE(1, 0, 1, 0)))),
-                                       screenir, screenmin, screenmax;
-                       if (numpoints <= 3) screeni = _mm_shuffle_epi32(screeni, _MM_SHUFFLE(2, 2, 1, 0));
-                       screenir = _mm_shuffle_epi32(screeni, _MM_SHUFFLE(1, 0, 3, 2)),
-                       screenmin = _mm_min_epi16(screeni, screenir);
-                       screenmax = _mm_max_epi16(screeni, screenir);
+                                                                                 _mm_cvttps_epi32(_mm_shuffle_ps(screen[2], numpoints <= 3 ? screen[2] : screen[3], _MM_SHUFFLE(1, 0, 1, 0)))),
+                                       screenir = _mm_shuffle_epi32(screeni, _MM_SHUFFLE(1, 0, 3, 2)), 
+                                       screenmin = _mm_min_epi16(screeni, screenir), 
+                                       screenmax = _mm_max_epi16(screeni, screenir);
                        screenmin = _mm_min_epi16(screenmin, _mm_shufflelo_epi16(screenmin, _MM_SHUFFLE(1, 0, 3, 2)));
                        screenmax = _mm_max_epi16(screenmax, _mm_shufflelo_epi16(screenmax, _MM_SHUFFLE(1, 0, 3, 2)));
                        screenmin = _mm_max_epi16(screenmin, _mm_setzero_si128());
-                       screenmax = _mm_min_epi16(screenmax, _mm_setr_epi16(width-1, height-1, 0, 0, 0, 0, 0, 0));
+                       screenmax = _mm_min_epi16(screenmax, fbmax);
                        // skip offscreen triangles
                        if (_mm_cvtsi128_si32(_mm_cmplt_epi16(screenmax, screenmin)) == -1)
                                continue;