aiura pedro

src/main.c

@@ -23,16 +23,13 @@ unsigned char palette[] =
 	0x7A,0x1C,0xAC,0xff,
 };
 
-void calc_normal(float* p1, float* p2, float* p3,float* normal, unsigned char n)
+void calc_normal(float* p1, float* p2, float* p3, float* normal, unsigned char n) {
-{
     float alpha;
     vec4 v1, v2, v3;
     vec4 u1, u2, u3;
 
-	switch (n)
+    switch (n) {
-	{
     case 3:
-
         glm_vec3_sub(p2, p1, v1);
         glm_vec3_sub(p3, p1, v2);
 
@@ -41,37 +38,19 @@ void calc_normal(float* p1, float* p2, float* p3,float* normal, unsigned char n)
         return;
 
     case 4:
-
-		/* 
-			In Grant-Shmidth we need 3 linearly independian vector that forms a basis, 
-			so we can have a ortonormal version of that basis, since, we must have  
-				v1 = p3 - p1
-				v2 = p2 - p1
-			Then v3 = p1, will most certantly be linerly independiant to v1 and v2.
-		*/
         glm_vec4_sub(p2, p1, v1);
         glm_vec4_sub(p3, p1, v2);
         glm_vec4_copy(p1, v3);
-		
-		/* Setup U1 */
-		{
         glm_vec4_copy(v1, u1);
-		}
-
-		/* Setup U2 */
         {
             vec4 proj;
-
             alpha = glm_vec4_dot(v2, u1) / glm_vec4_dot(u1, u1);
             glm_vec4_scale(u1, alpha, proj);
-
             glm_vec4_sub(v2, proj, u2);
         }
 		
-		/* Setup U3 */
         {
             vec4 proj1, proj2;
-
             alpha = glm_vec4_dot(v3, u1) / glm_vec4_dot(u1, u1);
             glm_vec4_scale(u1, alpha, proj1);
 
@@ -85,6 +64,52 @@ void calc_normal(float* p1, float* p2, float* p3,float* normal, unsigned char n)
         glm_vec4_copy(u3, normal);
         glm_vec4_normalize(normal);
         return;
+
+    default:
+        float** u = malloc((n - 1) * sizeof(float*));
+        for (unsigned char i = 0; i < n - 1; i++) {
+            u[i] = malloc(n * sizeof(float));
+        }
+
+        for (unsigned char i = 0; i < n - 1; i++) {
+            float* vi = malloc(n * sizeof(float));
+            for (unsigned char j = 0; j < n; j++) {
+                vi[j] = p2[j] - p1[j]; 
+            }
+
+            for (unsigned char j = 0; j < i; j++) {
+                float dot_vu = 0.0f, dot_uu = 0.0f;
+
+                for (unsigned char k = 0; k < n; k++) {
+                    dot_vu += vi[k] * u[j][k];
+                    dot_uu += u[j][k] * u[j][k];
+                }
+
+                for (unsigned char k = 0; k < n; k++) {
+                    vi[k] -= (dot_vu / dot_uu) * u[j][k];
+                }
+            }
+
+            memcpy(u[i], vi, n * sizeof(float));
+            free(vi);
+        }
+
+        memcpy(normal, u[n - 2], n * sizeof(float));
+
+        float norm = 0.0f;
+        for (unsigned char i = 0; i < n; i++) {
+            norm += normal[i] * normal[i];
+        }
+        norm = sqrtf(norm);
+        for (unsigned char i = 0; i < n; i++) {
+            normal[i] /= norm;
+        }
+
+        for (unsigned char i = 0; i < n - 1; i++) {
+            free(u[i]);
+        }
+        free(u);
+        return;
     }
 }