- Implemented anti-aliasing,

graphics/ass7/main.c

@@ -158,9 +158,9 @@ void
 ray_trace(void)
 {
     vec3    forward_vector, right_vector, up_vector;
-    int     i, j;
+    int     i, j, k, l;
     vec3    right_step, down_step;
-    float   image_plane_width, image_plane_height;
+    float   image_plane_width, image_plane_height, diff[2] = {0.25, 0.75};
     vec3    image_plane_topleft, image_plane_point;
     vec3    ray_direction;
     vec3    color;
@@ -203,16 +203,41 @@ ray_trace(void)
     {
         for (i = 0; i < framebuffer_width; i++)
         {
-            // Compute corresponding point on image plane
-            image_plane_point = v3_add(image_plane_topleft, v3_multiply(right_step, i+0.5));
-            image_plane_point = v3_add(image_plane_point, v3_multiply(down_step, j+0.5));
-
-            // Compute direction for shooting the ray
-            ray_direction = v3_subtract(image_plane_point, scene_camera_position);
-
-            // Determine ray color
-            color = ray_color(0, scene_camera_position, ray_direction);
-
+        	if( do_antialiasing)
+        	{
+		    	color.x = color.y = color.z = 0;
+		    	
+		    	for( k = 0; k < 2; k++ )
+		    	{
+					for( l = 0; l < 2; l++ )
+					{
+						// Compute corresponding point on image plane
+						image_plane_point = v3_add(image_plane_topleft, v3_multiply(right_step, i+diff[k]));
+						image_plane_point = v3_add(image_plane_point, v3_multiply(down_step, j+diff[l]));
+
+						// Compute direction for shooting the ray
+						ray_direction = v3_subtract(image_plane_point, scene_camera_position);
+
+						// Determine ray color
+						color = v3_add(color, ray_color(0, scene_camera_position, ray_direction));
+					}
+				}
+			
+				color = v3_multiply(color, 0.25);
+			}
+			else
+			{
+				// Compute corresponding point on image plane
+				image_plane_point = v3_add(image_plane_topleft, v3_multiply(right_step, i+0.5));
+				image_plane_point = v3_add(image_plane_point, v3_multiply(down_step, j+0.5));
+
+				// Compute direction for shooting the ray
+				ray_direction = v3_subtract(image_plane_point, scene_camera_position);
+
+				// Determine ray color
+				color = ray_color(0, scene_camera_position, ray_direction);
+			}
+			
             // Output pixel color
             put_pixel(i, j, color.x, color.y, color.z);
         }