Working with the Blin-Phong lighting. Fixed the symmetry between the normals. Starting working on shadows

kernels/ray_caster_kernel.cl

@@ -13,15 +13,98 @@ float4 white_light(float4 input, float3 light, int3 mask) {
 
 }
 
+bool cast_light_intersection_ray(
+	global char* map,
+	global int3* map_dim,
+	 float3 ray_dir,
+	 float3 ray_pos,
+	global float* lights,
+	global int* light_count 
+	
+	){
+
+	// Setup the voxel step based on what direction the ray is pointing
+	int3 voxel_step = { 1, 1, 1 };
+	voxel_step *= (ray_dir > 0) - (ray_dir < 0);
+
+	// Setup the voxel coords from the camera origin
+	int3 voxel = convert_int3(ray_pos);
+
+	// Delta T is the units a ray must travel along an axis in order to
+	// traverse an integer split
+	float3 delta_t = fabs(1.0f / ray_dir);
+
+	// offset is how far we are into a voxel, enables sub voxel movement
+	float3 offset = ((ray_pos) - floor(ray_pos)) * convert_float3(voxel_step);
+
+	// Intersection T is the collection of the next intersection points
+	// for all 3 axis XYZ.
+	float3 intersection_t = delta_t * offset;
+
+	// for negative values, wrap around the delta_t, rather not do this
+	// component wise, but it doesn't appear to want to work
+	if (intersection_t.x < 0) {
+		intersection_t.x += delta_t.x;
+	}
+	if (intersection_t.y < 0) {
+		intersection_t.y += delta_t.y;
+	}
+	if (intersection_t.z < 0) {
+		intersection_t.z += delta_t.z;
+	}
+
+	// Hard cut-off for how far the ray can travel
+	int max_dist = 800;
+	int dist = 0;
+
+	int3 face_mask = { 0, 0, 0 };
+
+	// Andrew Woo's raycasting algo
+	do {
+
+		// If we hit a voxel
+		int index = voxel.x + (*map_dim).x * (voxel.y + (*map_dim).z * (voxel.z));
+		int voxel_data = map[index];
+
+		if (voxel_data != 0) {
+			return true;
+		}
+
+		// Fancy no branch version of the logic step
+		face_mask = intersection_t.xyz <= min(intersection_t.yzx, intersection_t.zxy);
+		intersection_t += delta_t * fabs(convert_float3(face_mask.xyz));
+		voxel.xyz += voxel_step.xyz * face_mask.xyz;
+
+		// If the ray went out of bounds
+		int3 overshoot = voxel <= *map_dim;
+		int3 undershoot = voxel > 0;
+
+		if (overshoot.x == 0 || overshoot.y == 0 || overshoot.z == 0 || undershoot.x == 0 || undershoot.y == 0) {
+			return false;
+		}
+		if (undershoot.z == 0) {
+			return false;
+		}
+
+
+
+		dist++;
+
+	} while (dist < 700);
+
+	return false;
+}
 
 float4 view_light(float4 in_color, float3 light, float3 view, int3 mask) {
 	
 	float diffuse = max(dot(normalize(convert_float3(mask)), normalize(light)), 0.0f);
+	in_color += diffuse * 0.5;
+
 	if (dot(light, normalize(convert_float3(mask))) > 0.0)
 	{
 		float3 halfwayVector = normalize(normalize(light) + normalize(view));
 		float specTmp = max(dot(normalize(convert_float3(mask)), halfwayVector), 0.0f);
-		return in_color + pow(specTmp, 1.0f) * 0.01 +diffuse * 0.5;
+		in_color += pow(specTmp, 1.0f) * 0.01;
 	}
 
 	//float3 halfwayDir = normalize(normalize(view) + normalize(light));
@@ -31,9 +114,7 @@ float4 view_light(float4 in_color, float3 light, float3 view, int3 mask) {
 }
 
 
-void cast_ray(float3 ray_origin, float3 ray_direction) {
 
-}
 
 
 
@@ -154,6 +235,7 @@ __kernel void raycaster(
             ray_dir.z
     );
 
+    
 	// Setup the voxel step based on what direction the ray is pointing
     int3 voxel_step = {1, 1, 1};
 	voxel_step *= (ray_dir > 0) - (ray_dir < 0);
@@ -195,6 +277,7 @@ __kernel void raycaster(
 	float4 voxel_color = (float4)(0.25, 0.52, 0.30, 0.1);
 	float4 overshoot_color = { 0.25, 0.48, 0.52, 0.8 };
 	
+
 	// Andrew Woo's raycasting algo
     do {
 
@@ -221,13 +304,37 @@ __kernel void raycaster(
         int voxel_data = map[index];
 
 		if (voxel_data != 0) {
+
 			switch (voxel_data) {
 
 			case 5:
 
-				//write_imagef(image, pixel, (float4)(0.40, 0.00, 0.40, 0.2));
-				write_imagef(image, pixel, view_light(voxel_color, (convert_float3(voxel) + offset) - (float3)(lights[4], lights[5], lights[6]), (convert_float3(voxel) + offset) - (*cam_pos), face_mask));
-				//write_imagef(image, pixel, white_light(mix(fog_color, voxel_color, 1.0 - max((dist/700.0f) - 0.3f, (float)0)), (float3)(lights[7], lights[8], lights[9]), face_mask));
+				//	write_imagef(image, pixel, (float4)(0.90, 0.00, 0.40, 0.9));
+
+				if (!cast_light_intersection_ray(
+					map,
+					map_dim,
+					(float3)(lights[4], lights[5], lights[6]) - (convert_float3(voxel) + offset),
+					(convert_float3(voxel) + offset + convert_float3(face_mask)/10.0f),
+					lights,
+					light_count
+					)) {
+
+					write_imagef(image, pixel, (float4)(0.90, 0.00, 0.40, 0.9));
+					return;
+				}
+
+				write_imagef(
+					image,
+					pixel,
+					view_light(
+						voxel_color,
+						(convert_float3(voxel) + offset) - (float3)(lights[4], lights[5], lights[6]),
+						(convert_float3(voxel) + offset) - (*cam_pos),
+						face_mask * voxel_step
+						)
+					);
+
 				return;
 
 				float3 vox = convert_float3(voxel);
@@ -250,7 +357,7 @@ __kernel void raycaster(
 	
 
 			case 6:
-				write_imagef(image, pixel, view_light((float4)(0.0, 0.239, 0.419, 0.3), (convert_float3(voxel) + offset) - (float3)(lights[4], lights[5], lights[6]), (convert_float3(voxel) + offset) - (*cam_pos), face_mask));
+				write_imagef(image, pixel, view_light((float4)(0.0, 0.239, 0.419, 0.3), (convert_float3(voxel) + offset) - (float3)(lights[4], lights[5], lights[6]), (convert_float3(voxel) + offset) - (*cam_pos), face_mask * voxel_step));
 				//write_imagef(image, pixel, white_light(mix((float4)(0.73, 0.81, 0.89, 0.6), (float4)(0.0, 0.239, 0.419, 0.3), 1.0 - max((dist / 700.0f) - 0.3f, (float)0)), (float3)(lights[7], lights[8], lights[9]), face_mask));
 				return;
 

src/main.cpp

@@ -115,8 +115,8 @@ int main() {
 
 	// Light for the currently non functional Bling Phong shader
 	Light l;
-	l.direction_cartesian = sf::Vector3f(+1.5f, -1.2f, -0.5f);
-	l.position = sf::Vector3f(100.0f, 100.0f, 100.0f);
+	l.direction_cartesian = sf::Vector3f(-0.2f, -0.2f, -1.5f);
+	l.position = sf::Vector3f(100.0f, 100.0f, 500.0f);
 	l.rgbi = sf::Vector4f(0.3f, 0.4f, 0.3f, 1.0f);
 
 	std::vector<Light> light_vec;