Completed graphics assignment 6: ray tracing 1.

graphics/ass6/.gitignore

+main

graphics/ass6/main.c

 /* Computer Graphics, Assignment, Ray-tracing 1
  *
  * Student name .... Sander van Veen, Taddeüs Kroes
- * Student email ... sander@vo20.nl, taddeuskroes@gmail.com
- * Collegekaart .... 6167969,
+ * Student email ... sander@vo20.nl , taddeuskroes@gmail.com
+ * Collegekaart .... 6167969        , 6054129 
  * Date ............ 
  * Comments ........ 
  */
@@ -176,65 +176,42 @@ ray_trace(void)
     image_plane_width = image_plane_height * (1.0 * framebuffer_width 
 	                                          / framebuffer_height);
 
-	float l = image_plane_width * .5f, // measured from e along right_vector
-	      r = -l,
-	      b = image_plane_height * .5f, // measured from e along up_vector
-	      t = -b;
+	float scale = image_plane_width / framebuffer_width;
 
-	float u, v;
+	vec3 scaled_right = v3_multiply(right_vector, scale), 
+		 origin = scene_camera_position,
+	     next_line_diff = v3_subtract(
+	         v3_add(v3_multiply(up_vector, scale), 
+	                v3_multiply(right_vector, image_plane_width)),
+	         origin
+	     );
 
-	float frame_height_div = 1.0 / framebuffer_height,
-	      frame_width_div = 1.0 / framebuffer_width;
+	// Find midpoint and point 0,0
+	vec3 p = v3_subtract(
+	    v3_add(v3_add(origin, forward_vector),
+	           v3_multiply(up_vector, 0.5 * (image_plane_height - 0.5 * scale))),
+	    v3_multiply(right_vector, 0.5 * (image_plane_width - 0.5 * scale))
+	);
 
-	up_vector = v3_normalize(up_vector);
-
-	vec3 ray_o = scene_camera_position,
-	     ray_d = forward_vector;
-	//     e = scene_camera_position;
-	//	 e = v3_subtract(scene_camera_lookat, scene_camera_position);
-	
     // Loop over all pixels in the framebuffer
     for( j = 0; j < framebuffer_height; j++ )
     {
-        for( i = 0; i < framebuffer_width; i++ )
+		p = v3_subtract(p, origin);
+
+        for (i = 0; i < framebuffer_width; i++)
         {
-			// compute viewing ray
-			//u = l + (r - l) * (i + 0.5) * frame_width_div;
-			//v = b + (t - b) * (j + 0.5) * frame_height_div;
-			
-			// One unit distance, adjust to plane center and normalize
-			ray_d = v3_normalize(v3_create(
-				((i + .5f) * frame_width_div) + r,
-			    ((framebuffer_height - j + .5f) * frame_height_div) + t,
-			    1.f
-			));
-			
-			ray_d = v3_create(
-				right_vector.x * ray_d.x + up_vector.x * ray_d.y
-				+ forward_vector.x * ray_d.z,
-				right_vector.y * ray_d.x + up_vector.y * ray_d.y
-				+ forward_vector.y * ray_d.z,
-				right_vector.z * ray_d.x + up_vector.z * ray_d.y
-				+ forward_vector.z * ray_d.z
-			);
-
-			//ray_d = v3_normalize(v3_add(
-			//	ray_o,
-			//	v3_add(v3_multiply(right_vector, u), v3_multiply(up_vector, v))
-			//));
-
-			//if( i == 0 && j < 20 )
-			//	printf("d: [%f, %f, %f]\n", ray_d.x, ray_d.y, ray_d.z);
-
-			//ray_origin = v3_add(e, v3_add(v3_multiply(right_vector, u),
-			//                              v3_multiply(up_vector, v)));
-
-			color = ray_color(0, ray_o, ray_d); 
+            // Calculate point on the image plane that is center of the pixel
+            p = v3_add(p, scaled_right);
+            color = ray_color(0, origin, p);
 
             // Output pixel color
             put_pixel(i, j, color.x, color.y, color.z);
         }
-        sprintf(buf, "Ray-tracing ::: %.0f%% done",
+        
+		// Reset for the next line of pixels
+		p = v3_subtract(p, next_line_diff);
+        
+		sprintf(buf, "Ray-tracing ::: %.0f%% done",
 		        100.0 * j / framebuffer_height);
         glutSetWindowTitle(buf);
     }

graphics/ass6/shaders.c

 /* Computer Graphics, Assignment, Ray-tracing 1
  *
- * Student name ....
- * Student email ...
- * Collegekaart ....
+ * Student name .... Sander van Veen, Taddeüs Kroes
+ * Student email ... sander@vo20.nl , taddeuskroes@gmail.com
+ * Collegekaart .... 6167969        , 6054129 
  * Date ............
  * Comments ........
- *
- *
- * (always fill in these fields before submitting!!)
  */
 
 #include <math.h>
@@ -34,19 +31,84 @@ shade_constant(intersection_point ip)
 vec3
 shade_matte(intersection_point ip)
 {
-    return v3_create(1, 0, 0);
+	int i;
+
+	float c = .0f,
+	      dot;
+
+	vec3 shade;
+
+	for( i = 0; i < scene_num_lights; i++ )
+	{
+		shade = v3_normalize(v3_subtract(scene_lights[i].position, ip.p));
+		dot = v3_dotprod(ip.n, shade);
+
+		if( dot > .0f 
+		    && !shadow_check(v3_add(ip.p, v3_multiply(shade, .001f)), shade) )
+		{
+			c += scene_lights[i].intensity * dot;
+		}
+	}
+
+	c += scene_ambient_light;
+
+	// Make sure c is in range [0, 1]
+	if( c > 1.f )
+		c = 1.f;
+	
+	return v3_create(c, c, c);
 }
 
 vec3
 shade_blinn_phong(intersection_point ip)
 {
-    return v3_create(1, 0, 0);
+	int i, alpha = 50;
+	float c = .0f, dot, spec = .0f;
+	vec3 shade;
+
+	// Compute diffuse and specular illumination part
+	for (i = 0; i < scene_num_lights; i++)
+	{
+		shade = v3_normalize(v3_subtract(scene_lights[i].position, ip.p));
+		dot = v3_dotprod(ip.n, shade);
+
+		if( dot > .0f
+		    && !shadow_check(v3_add(ip.p, v3_multiply(shade, .001f)), shade) )
+		{
+			c += scene_lights[i].intensity * dot;
+		}
+
+		// Specular (color of a highlight)
+		spec += scene_lights[i].intensity *
+			pow(v3_dotprod(ip.n, v3_normalize(v3_add(ip.i, shade))), alpha);
+	}
+
+	// Apply k_d and k_s
+	c *= .8f;
+	spec *= .5f;
+
+	c += scene_ambient_light;
+
+	// Make sure color components are in [0, 1]
+	spec = fmin(spec, 1.f);
+	c = fmin(c + spec,  1.f);
+
+	return v3_create(c, spec, spec);
 }
 
 vec3
 shade_reflection(intersection_point ip)
 {
-    return v3_create(1, 0, 0);
+	// Compute reflection vector also to prevent self-reflection. Add a
+	// small bias to the surface point in the direction of the normal.
+	vec3 r = v3_normalize(
+	         v3_subtract(v3_multiply(ip.n, 2.f * v3_dotprod(ip.i, ip.n)), ip.i)
+	     );
+	
+	r = ray_color(ip.ray_level + 1, v3_add(ip.p, v3_multiply(ip.n, .001f)), r);
+
+	// Mix it with 75% matte shade
+	return v3_add(v3_multiply(shade_matte(ip), .75f), v3_multiply(r, .25f));
 }
 
 // Returns the shaded color for the given point to shade.