From 331056c2064f05bb25d0e8d72cdbd5f73dd5fbbb Mon Sep 17 00:00:00 2001
From: Dane Johnson <dane_johnson@ymail.com>
Date: Thu, 4 Mar 2021 14:49:48 -0600
Subject: [PATCH] Add ambient light from point lights

---
 core/Shaders/Shader.cpp    |  2 ++
 demo/exampleworld/main.lua |  3 ++-
 shaders/flat.vert          | 16 +++++++++++-----
 3 files changed, 15 insertions(+), 6 deletions(-)

diff --git a/core/Shaders/Shader.cpp b/core/Shaders/Shader.cpp
index d1e4c3b..6e8d5d4 100644
--- a/core/Shaders/Shader.cpp
+++ b/core/Shaders/Shader.cpp
@@ -91,6 +91,8 @@ void Shader::UpdatePointLights(PointLightList pointLights) {
 
     glUniform1f(glGetUniformLocation(id, Util::ShaderArrayName("pointLights", i, "radius").c_str()), pointLights[i]->GetRadius());
     glUniform1f(glGetUniformLocation(id, Util::ShaderArrayName("pointLights", i, "ambient").c_str()), pointLights[i]->GetAmbient());
+    glUniform1f(glGetUniformLocation(id, Util::ShaderArrayName("pointLights", i, "diffuse").c_str()), pointLights[i]->GetDiffuse());
+    glUniform1f(glGetUniformLocation(id, Util::ShaderArrayName("pointLights", i, "specular").c_str()), pointLights[i]->GetSpecular());
   }
 }
 
diff --git a/demo/exampleworld/main.lua b/demo/exampleworld/main.lua
index 68656b1..a5a78a6 100644
--- a/demo/exampleworld/main.lua
+++ b/demo/exampleworld/main.lua
@@ -185,7 +185,8 @@ function init_point_lights()
       pointLight:Translate(couch.Vector3(i * -10.0, 0, -10))
       pointLight:SetRadius(10.0)
       pointLight:SetColor(color)
-      pointLight:SetAmbient(1.0)
+      pointLight:SetAmbient(0.2)
+      pointLight:SetDiffuse(1.0)
       pointLight:SetSpecular(0.1)
       local lightBox = couch.Mesh.FromFile("../resources/cube.obj")
       lightBox:UniformScale(0.5);
diff --git a/shaders/flat.vert b/shaders/flat.vert
index 5f98d3c..dd7295c 100644
--- a/shaders/flat.vert
+++ b/shaders/flat.vert
@@ -55,13 +55,16 @@ struct Material {
 uniform DirectionalLight directionalLight;
 uniform Material material;
 
+float calcDiffuseIntensity(in vec3 direction, in vec3 normal) {
+  float diff = dot(normalize(direction), normalize(normal));
+  return max(diff, 0.0);
+}
+
 void calcDirectionalLight(in vec3 normal) {
   AMBIENT += directionalLight.ambient * directionalLight.color * material.ambient;
 
   vec3 direction = -(VIEW * vec4(directionalLight.direction, 0.0)).xyz;
-  float diff = dot(normalize(direction), normalize(normal));
-  diff = max(diff, 0.0);
-  DIFFUSE += directionalLight.diffuse * diff * directionalLight.color * material.diffuse;
+  DIFFUSE += directionalLight.diffuse * directionalLight.color * material.diffuse * calcDiffuseIntensity(direction, normal);
 
   vec3 viewDir = normalize((VIEW * MODEL * vec4(pos, 1.0)).xyz);
   vec3 reflectionDir = reflect(normalize(direction), normalize(normal));
@@ -72,10 +75,13 @@ void calcDirectionalLight(in vec3 normal) {
 }
 
 void calcPointLight(in vec3 normal, in PointLight pointLight) {
-  vec4 ray = VIEW * MODEL * vec4(pos, 1.0) - VIEW * vec4(pointLight.pos, 1.0);
-  float dist = length(ray);
+  vec3 direction = vec3(VIEW * vec4(pointLight.pos, 1.0) - VIEW * MODEL * vec4(pos, 1.0)).xyz;
+  float dist = length(direction);
+  
   float attenuation = max(1.0 - dist * dist / pointLight.radius / pointLight.radius, 0.0);
   AMBIENT += pointLight.color * material.ambient * pointLight.ambient * attenuation;
+
+  DIFFUSE += pointLight.color * pointLight.diffuse * material.diffuse * calcDiffuseIntensity(direction, normal);
 }
 
 void main() {