Basic Lighting

Added lighting in to the shader
Lighting model: Phong

shader.fs

@@ -1,11 +1,41 @@
 #version 460 core
 out vec4 FragColor;
 
+in vec3 Normal;
+in vec3 FragPos;
+
 uniform vec3 objectColor;
 uniform vec3 lightColor;
+uniform vec3 lightPos;
+uniform vec3 viewPos;
+
 
 
 void main()
 {
-    FragColor = vec4(lightColor * objectColor, 1.0);
+    // ambient lighting calculation
+    float ambientStrength = 0.1;
+    vec3 ambient = ambientStrength * lightColor;
+
+    // diffuse lighting calculation
+    vec3 norm = normalize(Normal);
+    vec3 lightDir = normalize(lightPos - FragPos);
+
+    float diff = max(dot(norm, lightDir), 0.0);
+    vec3 diffuse = diff * lightColor;
+
+    // specular lighting
+    float specularStrength = 0.5;
+    float shininess = 32;
+    vec3 viewDir = normalize(viewPos - FragPos);
+    vec3 reflectDir = reflect(-lightDir, norm);
+    
+    float spec = pow(max(dot(viewDir, reflectDir), 0.0), shininess);
+    vec3 specular = specularStrength * spec * lightColor;
+
+
+    // Calculate the result;
+    vec3 result = (ambient + diffuse + specular) * objectColor;
+
+    FragColor = vec4(result, 1.0);
 }

shader.vs

@@ -1,15 +1,19 @@
 #version 460 core
 layout (location=0) in vec3 aPos;
-
+layout (location=1) in vec3 aNormal;
 
 uniform mat4 model;
 uniform mat4 view;
 uniform mat4 projection;
 
+out vec3 FragPos;
+out vec3 Normal;
+
 
 
 void main(){
 
     gl_Position = projection * view * model * vec4(aPos , 1.0);
-    
+    FragPos = vec3(model * vec4(aPos, 1.0));
+    Normal = mat3(transpose(inverse(model))) * aNormal;    
 }

src/main.cpp

@@ -91,51 +91,50 @@ int main() {
    Shader lightshader("lightsource.vs", "lightsource.fs");
    Shader shader ("shader.vs", "shader.fs");
 
-  float vertices[] = {
+float vertices[] = {
-        -0.5f, -0.5f, -0.5f, 
+    -0.5f, -0.5f, -0.5f,  0.0f,  0.0f, -1.0f,
-         0.5f, -0.5f, -0.5f,  
+     0.5f, -0.5f, -0.5f,  0.0f,  0.0f, -1.0f, 
-         0.5f,  0.5f, -0.5f,  
+     0.5f,  0.5f, -0.5f,  0.0f,  0.0f, -1.0f, 
-         0.5f,  0.5f, -0.5f,  
+     0.5f,  0.5f, -0.5f,  0.0f,  0.0f, -1.0f, 
-        -0.5f,  0.5f, -0.5f, 
+    -0.5f,  0.5f, -0.5f,  0.0f,  0.0f, -1.0f, 
-        -0.5f, -0.5f, -0.5f, 
+    -0.5f, -0.5f, -0.5f,  0.0f,  0.0f, -1.0f, 
 
-        -0.5f, -0.5f,  0.5f, 
+    -0.5f, -0.5f,  0.5f,  0.0f,  0.0f, 1.0f,
-         0.5f, -0.5f,  0.5f,  
+     0.5f, -0.5f,  0.5f,  0.0f,  0.0f, 1.0f,
-         0.5f,  0.5f,  0.5f,  
+     0.5f,  0.5f,  0.5f,  0.0f,  0.0f, 1.0f,
-         0.5f,  0.5f,  0.5f,  
+     0.5f,  0.5f,  0.5f,  0.0f,  0.0f, 1.0f,
-        -0.5f,  0.5f,  0.5f, 
+    -0.5f,  0.5f,  0.5f,  0.0f,  0.0f, 1.0f,
-        -0.5f, -0.5f,  0.5f, 
+    -0.5f, -0.5f,  0.5f,  0.0f,  0.0f, 1.0f,
 
-        -0.5f,  0.5f,  0.5f, 
+    -0.5f,  0.5f,  0.5f, -1.0f,  0.0f,  0.0f,
-        -0.5f,  0.5f, -0.5f, 
+    -0.5f,  0.5f, -0.5f, -1.0f,  0.0f,  0.0f,
-        -0.5f, -0.5f, -0.5f, 
+    -0.5f, -0.5f, -0.5f, -1.0f,  0.0f,  0.0f,
-        -0.5f, -0.5f, -0.5f, 
+    -0.5f, -0.5f, -0.5f, -1.0f,  0.0f,  0.0f,
-        -0.5f, -0.5f,  0.5f, 
+    -0.5f, -0.5f,  0.5f, -1.0f,  0.0f,  0.0f,
-        -0.5f,  0.5f,  0.5f, 
+    -0.5f,  0.5f,  0.5f, -1.0f,  0.0f,  0.0f,
 
-         0.5f,  0.5f,  0.5f,  
+     0.5f,  0.5f,  0.5f,  1.0f,  0.0f,  0.0f,
-         0.5f,  0.5f, -0.5f,  
+     0.5f,  0.5f, -0.5f,  1.0f,  0.0f,  0.0f,
-         0.5f, -0.5f, -0.5f,  
+     0.5f, -0.5f, -0.5f,  1.0f,  0.0f,  0.0f,
-         0.5f, -0.5f, -0.5f,  
+     0.5f, -0.5f, -0.5f,  1.0f,  0.0f,  0.0f,
-         0.5f, -0.5f,  0.5f,  
+     0.5f, -0.5f,  0.5f,  1.0f,  0.0f,  0.0f,
-         0.5f,  0.5f,  0.5f,  
+     0.5f,  0.5f,  0.5f,  1.0f,  0.0f,  0.0f,
 
-        -0.5f, -0.5f, -0.5f, 
+    -0.5f, -0.5f, -0.5f,  0.0f, -1.0f,  0.0f,
-         0.5f, -0.5f, -0.5f,  
+     0.5f, -0.5f, -0.5f,  0.0f, -1.0f,  0.0f,
-         0.5f, -0.5f,  0.5f,  
+     0.5f, -0.5f,  0.5f,  0.0f, -1.0f,  0.0f,
-         0.5f, -0.5f,  0.5f,  
+     0.5f, -0.5f,  0.5f,  0.0f, -1.0f,  0.0f,
-        -0.5f, -0.5f,  0.5f, 
+    -0.5f, -0.5f,  0.5f,  0.0f, -1.0f,  0.0f,
-        -0.5f, -0.5f, -0.5f, 
+    -0.5f, -0.5f, -0.5f,  0.0f, -1.0f,  0.0f,
 
-        -0.5f,  0.5f, -0.5f, 
+    -0.5f,  0.5f, -0.5f,  0.0f,  1.0f,  0.0f,
-         0.5f,  0.5f, -0.5f,  
+     0.5f,  0.5f, -0.5f,  0.0f,  1.0f,  0.0f,
-         0.5f,  0.5f,  0.5f,  
+     0.5f,  0.5f,  0.5f,  0.0f,  1.0f,  0.0f,
-         0.5f,  0.5f,  0.5f,  
+     0.5f,  0.5f,  0.5f,  0.0f,  1.0f,  0.0f,
-        -0.5f,  0.5f,  0.5f, 
+    -0.5f,  0.5f,  0.5f,  0.0f,  1.0f,  0.0f,
-        -0.5f,  0.5f, -0.5f, 
+    -0.5f,  0.5f, -0.5f,  0.0f,  1.0f,  0.0f
-    };
+};
 
-#pragma region Objects
    unsigned int VBO, VAO;
    glGenVertexArrays(1, &VAO);
    glGenBuffers(1, &VBO);
@@ -146,22 +145,21 @@ int main() {
    glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
 
     // position attribute
-    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 3 * sizeof(float), (void*)0);
+    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 6 * sizeof(float), (void*)0);
     glEnableVertexAttribArray(0);
 
+   glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 6 * sizeof(float), (void*) (3*sizeof(float)));
+   glEnableVertexAttribArray(1);
+
    unsigned int lightVAO;
    glGenVertexArrays(1, &lightVAO);
    glBindVertexArray(lightVAO);
 
    glBindBuffer(GL_ARRAY_BUFFER, VBO);
 
-   glVertexAttribPointer(0,3,GL_FLOAT,GL_FALSE, 3* sizeof(float), (void*) 0);
+   glVertexAttribPointer(0,3,GL_FLOAT,GL_FALSE, 6* sizeof(float), (void*) 0);
    glEnableVertexAttribArray(0);
 
-#pragma endregion
-
-
-
 
 glfwSetInputMode(window, GLFW_CURSOR, GLFW_CURSOR_DISABLED); 
 glfwSetCursorPosCallback(window, mouse_callback); 
@@ -189,10 +187,19 @@ while(!glfwWindowShouldClose(window))
    
    projection = glm::perspective(glm::radians(camera.Zoom), (float)800 / (float)600, 0.1f, 100.0f);
    
+   float orbital_speed = .4 ; 
+
+   // move light around 
+   lightpos.x = 1.0 + sin(glfwGetTime()) * 2.0f;
+   lightpos.y = sin(glfwGetTime() / 2.0f) * 1.0f;
+
+   
    // draw cubes
    shader.use();
    shader.setVec3("objectColor", glm::vec3( 1.0f, 0.5, 0.31f));
    shader.setVec3("lightColor",glm::vec3( 1.0f, 1.0f, 1.0f));
+   shader.setVec3("lightPos", lightpos);
+   shader.setVec3("viewPos", camera.Position);
 
    shader.setMat4("view", view);
    shader.setMat4("projection", projection);