From 345ae95835b536c24cdb5368d523a41d6fa4c887 Mon Sep 17 00:00:00 2001
From: Nigel <nigelbarink@hotmail.com>
Date: Wed, 16 Feb 2022 19:57:18 +0100
Subject: [PATCH] Directional light implementation

---
 shader.fs    |  6 ++++--
 src/main.cpp | 35 ++++++++++++++++++++++++++++-------
 2 files changed, 32 insertions(+), 9 deletions(-)

diff --git a/shader.fs b/shader.fs
index 4cb5bc7..7560297 100644
--- a/shader.fs
+++ b/shader.fs
@@ -12,7 +12,9 @@ struct Material {
 };
 
 struct Light{
-    vec3 position;
+    // vec3 position; // Not neccessary when using directional lights.
+
+    vec3 direction;
 
     vec3 ambient;
     vec3 diffuse;
@@ -34,7 +36,7 @@ void main()
 
     // diffuse lighting calculation
     vec3 norm = normalize(Normal);
-    vec3 lightDir = normalize(light.position - FragPos);
+    vec3 lightDir = normalize(-light.direction); // simplified with directional lights normalize(light.position - FragPos);
 
     float diff = max(dot(norm, lightDir), 0.0);
     vec3 diffuse =  light.diffuse *  diff * vec3(texture(material.diffuse, TexCoords));
diff --git a/src/main.cpp b/src/main.cpp
index cf9de71..ea31c0a 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -20,7 +20,7 @@ Camera camera(glm::vec3(0.0f, 0.0f, 8.0f));
 float lastX = 400, lastY = 300;
 bool firstMouse  = true;
 
-glm::vec3 lightpos(1.2f, 1.0f, 2.0f);
+glm::vec3 lightpos(-0.2f, -1.0f, -0.3f);
 
 void framebuffer_size_callback(GLFWwindow* window, int width, int height) {
    glViewport(0,0, width, height);
@@ -136,6 +136,19 @@ float vertices[] = {
     -0.5f,  0.5f, -0.5f,  0.0f,  1.0f,  0.0f,  0.0f, 1.0f
 };
 
+glm::vec3 cubePositions[] = {
+    glm::vec3( 0.0f,  0.0f,  0.0f),
+    glm::vec3( 2.0f,  5.0f, -15.0f),
+    glm::vec3(-1.5f, -2.2f, -2.5f),
+    glm::vec3(-3.8f, -2.0f, -12.3f),
+    glm::vec3( 2.4f, -0.4f, -3.5f),
+    glm::vec3(-1.7f,  3.0f, -7.5f),
+    glm::vec3( 1.3f, -2.0f, -2.5f),
+    glm::vec3( 1.5f,  2.0f, -2.5f),
+    glm::vec3( 1.5f,  0.2f, -1.5f),
+    glm::vec3(-1.3f,  1.0f, -1.5f)
+};
+
    unsigned int VBO, VAO;
    glGenVertexArrays(1, &VAO);
    glGenBuffers(1, &VBO);
@@ -233,9 +246,7 @@ while(!glfwWindowShouldClose(window))
    
    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
@@ -248,7 +259,7 @@ while(!glfwWindowShouldClose(window))
 
 
 
-   shader.setVec3("light.position", lightpos);
+   shader.setVec3("light.direction", lightpos);
 
    shader.setVec3("light.ambient", glm::vec3(0.2f, 0.2f, 0.2f));
    shader.setVec3("light.diffuse", glm::vec3(0.5f, 0.5f, 0.5f));
@@ -271,8 +282,18 @@ while(!glfwWindowShouldClose(window))
    glActiveTexture(GL_TEXTURE1);
    glBindTexture(GL_TEXTURE_2D, specularMap);
 
-   glBindVertexArray(VAO);
-   glDrawArrays(GL_TRIANGLES, 0, 36);
+   for( unsigned int i = 0; i < 10; i++ ){
+      glm::mat4 model = glm::mat4(1.0f);
+      model = glm::translate(model , cubePositions[i]);
+      float angle = 20.0f * i;
+      model = glm::rotate(model, glm::radians(angle), glm::vec3(1.0f, 0.3f, 0.5f));
+      shader.setMat4("model", model);
+
+      glBindVertexArray(VAO);
+      glDrawArrays(GL_TRIANGLES, 0, 36);
+
+
+   }