More clipping work

GL/clip.c

@@ -1,4 +1,6 @@
 #include <float.h>
+#include <stdio.h>
+
 #include "clip.h"
 
 ClipResult clipLineToNearZ(const float* v1, const float* v2, const float dist, float* vout, float* t) {
@@ -45,7 +47,7 @@ TriangleClipResult clipTriangleToNearZ(
      */
 
     typedef unsigned char uint8;
-    uint8 visible = ((uint8) v1->z < plane_dist) | ((uint8) v2->z < plane_dist) << 1 | ((uint8) v3->z < plane_dist) << 2;
+    uint8 visible = (v1->z >= plane_dist) ? 1 : 0 | (v2->z >= plane_dist) ? 2 : 0 | (v3->z >= plane_dist) ? 4 : 0;
 
     switch(visible) {
     case 0b000:
@@ -67,27 +69,31 @@ TriangleClipResult clipTriangleToNearZ(
     default: {
         /* One vertex is visible */
         /* This is the "easy" case, we simply find the vertex which is visible, and clip the lines to the other 2 against the plane */
+        fprintf(stderr, "Clipping triangle\n");
 
         pvr_vertex_t tmp1, tmp2;
         float t1, t2;
 
         if(visible == 0b001) {
-            ClipResult l1 = clipLineToNearZ(&v1->x, &v2->x, plane_dist, &tmp1, &t1);
+            ClipResult l1 = clipLineToNearZ(&v1->x, &v2->x, plane_dist, &tmp1.x, &t1);
-            ClipResult l2 = clipLineToNearZ(&v1->x, &v3->x, plane_dist, &tmp2, &t2);
+            ClipResult l2 = clipLineToNearZ(&v1->x, &v3->x, plane_dist, &tmp2.x, &t2);
+
+            fprintf(stderr, "New V2: %f, %f, %f. T: %f\n", tmp1.x, tmp1.y, tmp1.z, t1);
+            fprintf(stderr, "New V3: %f, %f, %f. T: %f\n", tmp2.x, tmp2.y, tmp2.z, t2);
 
             *v1out = *v1;
             *v2out = tmp1;
             *v3out = tmp2;
         } else if(visible == 0b010) {
-            ClipResult l1 = clipLineToNearZ(&v2->x, &v1->x, plane_dist, &tmp1, &t1);
+            ClipResult l1 = clipLineToNearZ(&v2->x, &v1->x, plane_dist, &tmp1.x, &t1);
-            ClipResult l2 = clipLineToNearZ(&v2->x, &v3->x, plane_dist, &tmp2, &t2);
+            ClipResult l2 = clipLineToNearZ(&v2->x, &v3->x, plane_dist, &tmp2.x, &t2);
 
             *v1out = tmp1;
             *v2out = *v2;
             *v3out = tmp2;
         } else {
-            ClipResult l1 = clipLineToNearZ(&v3->x, &v1->x, plane_dist, &tmp1, &t1);
+            ClipResult l1 = clipLineToNearZ(&v3->x, &v1->x, plane_dist, &tmp1.x, &t1);
-            ClipResult l2 = clipLineToNearZ(&v3->x, &v2->x, plane_dist, &tmp2, &t2);
+            ClipResult l2 = clipLineToNearZ(&v3->x, &v2->x, plane_dist, &tmp2.x, &t2);
 
             *v1out = tmp1;
             *v2out = tmp2;

GL/clip.h

@@ -19,6 +19,8 @@ typedef struct {
     uint32  argb;               /**< \brief Vertex color */
     uint32  oargb;              /**< \brief Vertex offset color */
 } pvr_vertex_t;
+#else
+#include <dc/pvr.h>
 #endif
 
 typedef enum {

GL/draw.c

@@ -1,4 +1,5 @@
 #include <stdio.h>
+#include <string.h>
 
 #include "../include/gl.h"
 #include "../include/glext.h"
@@ -190,8 +191,8 @@ inline void transformNormalToEyeSpace(GLfloat* normal) {
     mat_trans_normal3(normal[0], normal[1], normal[2]);
 }
 
-/* If this has a value other than zero, it must be negative! */
+/* If this has a value other than zero, it must be positive! */
-#define NEAR_DEPTH 0.0f
+#define NEAR_DEPTH 0.0001f
 
 static void submitVertices(GLenum mode, GLsizei first, GLsizei count, GLenum type, const GLvoid* indices) {
     static GLfloat normal[3] = {0.0f, 0.0f, -1.0f};
@@ -322,6 +323,8 @@ static void submitVertices(GLenum mode, GLsizei first, GLsizei count, GLenum typ
 
         _applyRenderMatrix(); /* Apply the Render Matrix Stack */
 
+        float W_stash[3];
+
         // FIXME: Don't perspective divide!
         transformVertex(&vertex->x, &vertex->x, &vertex->y, &vertex->z);
 
@@ -343,7 +346,7 @@ static void submitVertices(GLenum mode, GLsizei first, GLsizei count, GLenum typ
         // Store this for the clip stash
         pvr_vertex_t original_vertex = *((pvr_vertex_t*) dst);
 
-        if(rel >= 2) {            
+        if(rel >= 2) {
             /* We have at least one complete triangle, let's start clipping! */
             pvr_vertex_t* v1 = (pvr_vertex_t*) &clip_stash[0];
             pvr_vertex_t* v2 = (pvr_vertex_t*) &clip_stash[1];
@@ -380,7 +383,6 @@ static void submitVertices(GLenum mode, GLsizei first, GLsizei count, GLenum typ
                 /*
                  * Two vertices were behind the clip plane, we just manipulated them.
                    we have to end the triangle strip here and pick up next vertex */
-
                 v3out->flags = PVR_CMD_VERTEX_EOL;
 
                 /* Now we push back the original 2 vertices, so that the next triangle strip will be properly
@@ -390,8 +392,9 @@ static void submitVertices(GLenum mode, GLsizei first, GLsizei count, GLenum typ
                     activePolyList()->vector.size + 2
                 );
 
-                *(++dst) = (PVRCommand) clip_stash[1];
+                /* clip_stash[1] holds the previous vertex, original_vertex holds the current one */
-                *(++dst) = (PVRCommand) original_vertex;
+                memcpy(++dst, &clip_stash[1], sizeof(PVRCommand));
+                memcpy(++dst, &original_vertex, sizeof(PVRCommand));
 
             } else if(ret == TRIANGLE_CLIP_RESULT_ALTERED_AND_CREATED_VERTEX) {
                 /* One vertex was behind the clip plane, we need to create another triangle */
@@ -407,7 +410,7 @@ static void submitVertices(GLenum mode, GLsizei first, GLsizei count, GLenum typ
         clip_stash[0] = clip_stash[1];
         clip_stash[1] = original_vertex;
 
-        //FIXME: Peform perspective division
+        //FIXME: Perform perspective division
 
         ++dst;
     }

samples/Makefile

@@ -14,3 +14,5 @@ all:
 	$(KOS_MAKE) -C ortho2d all
 	$(KOS_MAKE) -C lerabot01 all
 	$(KOS_MAKE) -C zclip all
+	$(KOS_MAKE) -C zclip1 all
+	$(KOS_MAKE) -C zclip2 all