Adjust shaders for normal mapping

Signed-off-by: Tobias Frisch <tfrisch@uni-koblenz.de>

demos/NormalMapping/shaders/NormalMapping.frag

@@ -33,20 +33,37 @@ layout(set=0, binding=4) uniform texturePropsBuffer {
 	int useColorTexture;
 };
 
-layout(location = 0) in vec3 passLightVector;
-layout(location = 1) in vec3 passEyeVector;
-layout(location = 2) in vec2 passUV;
+layout(location = 0) in vec3 passPosition;
+layout(location = 1) in vec3 passNormal;
+layout(location = 2) in vec3 passTangent;
+layout(location = 3) in vec2 passUV;
 
 layout(location = 0) out vec4 fragmentColor;
 
 void main(){
-    
+    vec3 normal = normalize(passNormal);
+    vec3 tangent = normalize(passTangent);
+    vec3 bitangent = cross(tangent, normal);
+
     /***************** Diffuse ******************************************************/
     // local normal, in tangent space
-    vec3 normal = texture(sampler2D(normalTexture, colorSampler), passUV).rgb * 2.0 - 1.0;
+    vec3 normalWeights = texture(sampler2D(normalTexture, colorSampler), passUV).rgb * 2.0 - 1.0;
+
+    mat3 tbn = transpose(mat3(
+        tangent,
+        bitangent,
+        normal
+    ));
+
+    normal = tbn * normalWeights;
 
-    // direction of the light (from the fragment to the light) in tangent space
-    vec3 lightVector = normalize(passLightVector);
+    vec3 lightVector;
+    vec3 light_camcoord = (light.pos).xyz;
+    if (light.pos.w > 0.001f) {
+        lightVector = normalize(light_camcoord - passPosition);
+    } else {
+        lightVector = normalize(light_camcoord);
+    }
 
     //compute the diffuse lighting factor
     float cos_phi = max(dot(normal, lightVector), 0);
@@ -56,7 +73,7 @@ void main(){
     vec3 reflection = normalize(reflect(-lightVector, normal));
 
     // eye vector in tangent space
-    vec3 eyeVector = normalize(passEyeVector);
+    vec3 eyeVector = normalize(-passPosition);
 
     // compute the specular lighting factor
     float cos_psi_n = pow(max(dot(reflection, eyeVector), 0.0f), mat.shininess);

demos/NormalMapping/shaders/NormalMapping.vert

@@ -5,8 +5,6 @@ layout(location = 1) in vec3 normal;
 layout(location = 2) in vec2 uv;
 layout(location = 3) in vec3 tangent;
 
-//vec3 tangent = vec3(0);
-
 layout(set=0, binding=0) uniform matrixBuffer {
 	mat4 modelMatrix;
 	mat4 viewMatrix;
@@ -26,42 +24,24 @@ layout(set=0, binding=2) uniform lightBuffer {
 	vec3 lightAmbient;
 };
 
-layout(location = 0) out vec3 passLightVector;
-layout(location = 1) out vec3 passEyeVector;
-layout(location = 2) out vec2 passUV;
+layout(location = 0) out vec3 passPosition;
+layout(location = 1) out vec3 passNormal;
+layout(location = 2) out vec3 passTangent;
+layout(location = 3) out vec2 passUV;
 
-void main(){
+void main() {
     
     gl_Position = projectionMatrix * viewMatrix * modelMatrix * vec4(position, 1);
 
-    /*********** Calculate matrix that goes from camera space to tangent space **********/
-    mat4 normalMatrix = transpose(inverse(viewMatrix * modelMatrix));
-	vec3 normal_cs = normalize((normalMatrix * vec4(normal,0)).xyz);
-	vec3 tangent_cs = normalize((normalMatrix * vec4(tangent,0)).xyz);
-	vec3 bitangent_cs = cross(tangent_cs, normal_cs);
-
-    mat3 tbn = transpose(mat3(
-        tangent_cs,
-        bitangent_cs,
-        normal_cs
-    ));
-
-    /*********** Calculate position in camera space *************************************/
-	vec3 position_cs = (viewMatrix * modelMatrix * vec4(position, 1)).xyz;
-
-    /*********** Calculate light vector (tangent space) *********************************/
-    // light position in world coordinates
-	vec3 lightPosition_cs = (light.pos).xyz;
-
-    // calcluate vector that goes from the vertex to the light, in tangent space
-	passLightVector = tbn * normalize(lightPosition_cs - position_cs);
-
-    /*********** Calculate eye vector (tangent space) **********************************/
-    // calculate eye vector in camera space
-    vec3 eye_cs = normalize(-position_cs);
+	//transform the position correctly into view space
+	//and pass it to the fragment shader
+	passPosition = (viewMatrix * modelMatrix * vec4(position, 1)).xyz;
 
-    // calculate eye vector in tangent space
-    passEyeVector = tbn * eye_cs;
+	//transform the normal and tangent correctly into view space
+	//and pass it to the fragment shader
+	mat3 normalMatrix = mat3(transpose(inverse(viewMatrix * modelMatrix)));
+	passNormal = normalize(normalMatrix * normal);
+	passTangent = normalize(normalMatrix * tangent);
 
     /*********** Pass uv of the vertex *************************************************/
 	// no special space for this one