Refine code

Author: zauonlok

renderer/core/graphics.c

@@ -326,12 +326,10 @@ static int is_back_facing(vec3_t ndc_coords[3]) {
  * for viewport transformation, see subsection 2.12.1 of
  * https://www.khronos.org/registry/OpenGL/specs/es/2.0/es_full_spec_2.0.pdf
  */
-static vec3_t viewport_transform(int width_, int height_, vec3_t ndc_coord) {
-    float width = (float)width_;
-    float height = (float)height_;
-    float x = (ndc_coord.x + 1) * 0.5f * width;   /* [-1, 1] -> [0, w] */
-    float y = (ndc_coord.y + 1) * 0.5f * height;  /* [-1, 1] -> [0, h] */
-    float z = (ndc_coord.z + 1) * 0.5f;           /* [-1, 1] -> [0, 1] */
+static vec3_t viewport_transform(int width, int height, vec3_t ndc_coord) {
+    float x = (ndc_coord.x + 1) * 0.5f * (float)width;   /* [-1, 1] -> [0, w] */
+    float y = (ndc_coord.y + 1) * 0.5f * (float)height;  /* [-1, 1] -> [0, h] */
+    float z = (ndc_coord.z + 1) * 0.5f;                  /* [-1, 1] -> [0, 1] */
     return vec3_new(x, y, z);
 }
 
@@ -346,11 +344,8 @@ static int max_integer(int a, int b) {
 }
 
 static bbox_t find_bounding_box(vec2_t abc[3], int width, int height) {
-    vec2_t a = abc[0];
-    vec2_t b = abc[1];
-    vec2_t c = abc[2];
-    vec2_t min = vec2_min(vec2_min(a, b), c);
-    vec2_t max = vec2_max(vec2_max(a, b), c);
+    vec2_t min = vec2_min(vec2_min(abc[0], abc[1]), abc[2]);
+    vec2_t max = vec2_max(vec2_max(abc[0], abc[1]), abc[2]);
     bbox_t bbox;
     bbox.min_x = max_integer((int)ceil(min.x), 0);
     bbox.min_y = max_integer((int)ceil(min.y), 0);
@@ -397,10 +392,10 @@ static vec3_t calculate_weights(vec2_t abc[3], vec2_t p) {
  * https://www.khronos.org/registry/OpenGL/specs/es/2.0/es_full_spec_2.0.pdf
  */
 static float interpolate_depth(float screen_depths[3], vec3_t weights) {
-    float depth0 = screen_depths[0];
-    float depth1 = screen_depths[1];
-    float depth2 = screen_depths[2];
-    return depth0 * weights.x + depth1 * weights.y + depth2 * weights.z;
+    float depth0 = screen_depths[0] * weights.x;
+    float depth1 = screen_depths[1] * weights.y;
+    float depth2 = screen_depths[2] * weights.z;
+    return depth0 + depth1 + depth2;
 }
 
 /*