From 2d4e2b972762a6bd02297336083043e99645a8db Mon Sep 17 00:00:00 2001
From: Anselme <anselme16@hotmail.fr>
Date: Wed, 1 Jul 2015 21:41:22 +0200
Subject: [PATCH] better blinn-phong, directionnal light at sun position

---
 lights.cpp        |  5 +++--
 lights.h          |  4 ++--
 myglwidget.cpp    |  2 +-
 phong.frag        | 17 ++++++++++++-----
 phong.vert        | 24 ++++++++++++++++++------
 phongmaterial.cpp |  2 +-
 scene.cpp         |  4 ++--
 shader.cpp        |  2 +-
 shader.h          |  2 +-
 9 files changed, 41 insertions(+), 21 deletions(-)

diff --git a/lights.cpp b/lights.cpp
index c7d004e..695b524 100644
--- a/lights.cpp
+++ b/lights.cpp
@@ -12,8 +12,9 @@ void Lights::addLight(const glm::vec3 &myPosition, const glm::vec3 myColor)
     }
 }
 
-void Lights::bind(GLuint location, Shader* shader)
+void Lights::bind(GLuint lightsLocation, GLuint nbLocation, Shader* shader)
 {
     if(lights.size() > 0)
-        shader->bindVec3Array(location, (glm::vec3*)lights.data(), lights.size()*2);
+        shader->bindVec3Array(lightsLocation, (glm::vec3*)lights.data(), lights.size()*2);
+    shader->bindInteger(nbLocation, (GLuint)lights.size());
 }
diff --git a/lights.h b/lights.h
index cd266c8..8d035ef 100644
--- a/lights.h
+++ b/lights.h
@@ -5,7 +5,7 @@
 #include <glew/glew.h>
 #include <vector>
 
-#define MAX_LIGHTS 16
+#define MAX_LIGHTS 8
 
 class Shader;
 
@@ -21,7 +21,7 @@ private:
     std::vector<Light> lights;
 public:
     void addLight(const glm::vec3 &myPosition = glm::vec3(0), const glm::vec3 myColor = glm::vec3(1));
-    void bind(GLuint location, Shader* shader);
+    void bind(GLuint lightsLocation, GLuint nbLocation, Shader* shader);
 };
 
 #endif // LIGHT_H
diff --git a/myglwidget.cpp b/myglwidget.cpp
index f192864..0baeb6e 100644
--- a/myglwidget.cpp
+++ b/myglwidget.cpp
@@ -58,7 +58,7 @@ Scene* MyGLWidget::buildScene()
 
     scene->addEntity(myGrid, mat);
 
-    scene->addDirectionnalLight(glm::vec3(2, 3, 4), glm::vec3(0.6f, 0.5f, 0.4f));
+    scene->addDirectionnalLight(glm::vec3(6, 4, -4), glm::vec3(0.7f, 0.6f, 0.4f)); // sun
 
     return scene;
 }
diff --git a/phong.frag b/phong.frag
index f4c1ce3..af1d944 100644
--- a/phong.frag
+++ b/phong.frag
@@ -5,8 +5,10 @@ uniform vec3 materialKd;
 uniform vec3 materialKs;
 uniform float materialNs;
 
-uniform vec3 dirLights[32];
-uniform vec3 pointLights[32];
+uniform int nbDirLights;
+uniform vec3 dirLights[16];
+uniform int nbPointLights;
+uniform vec3 pointLights[16];
 
 // texture
 uniform sampler2D baseTexture;
@@ -15,8 +17,8 @@ uniform sampler2D baseTexture;
 in vec3 varNormal;
 in vec2 varTexCoord;
 
-in vec3 lightDirInView[16];
-in vec3 halfVecInView[16];
+in vec3 lightDirInView[8];
+in vec3 halfVecInView[8];
 
 // resultat
 layout(location = 0)out vec4 outColor;
@@ -36,8 +38,13 @@ vec3 computeLight(in vec3 kd, in vec3 ks, in float ns, in vec3 color, in vec3 no
 }
 
 void main(void) {
+	int i;
 	vec3 kd = vec3(texture2D(baseTexture, varTexCoord));
-	vec3 light = 0.1f*kd + computeLight(kd, materialKs, materialNs, dirLights[1], varNormal, lightDirInView[0], halfVecInView[0]);
+	vec3 light = 0.1f*kd;
+	for(i=0; i<nbDirLights && i<8; ++i)
+		light += computeLight(kd, materialKs, materialNs, dirLights[i*2+1], varNormal, lightDirInView[i], halfVecInView[i]);
+	for(i=0; i<nbPointLights && i+nbDirLights<8; ++i)
+		light += computeLight(kd, materialKs, materialNs, pointLights[i*2+1], varNormal, lightDirInView[nbDirLights+i], halfVecInView[nbDirLights+i]);
 
 	outColor = vec4(light, 1);
 }
diff --git a/phong.vert b/phong.vert
index 5d71eea..253a778 100644
--- a/phong.vert
+++ b/phong.vert
@@ -6,27 +6,39 @@ uniform mat4 MVP;
 uniform mat4 normalMatrix;
 uniform mat4 viewMatrix;
 
-uniform vec3 dirLights[32];
-uniform vec3 pointLights[32];
+uniform int nbDirLights;
+uniform vec3 dirLights[16];
+uniform int nbPointLights;
+uniform vec3 pointLights[16];
 
 layout(location = 0)in vec3 inPosition;
 layout(location = 1)in vec3 inNormal;
 layout(location = 2)in vec4 inTexCoord;
 
-out vec3 lightDirInView[16];
-out vec3 halfVecInView[16];
+out vec3 lightDirInView[8];
+out vec3 halfVecInView[8];
 
 out vec3 varNormal;
 out vec2 varTexCoord;
 
-void computeLightingVectorsInView(in vec3 posInView, in vec3 lightPosition, out vec3 lightDir, out vec3 halfVec){
+void computeDirectionnalLightingVectorsInView(in vec3 posInView, in vec3 lightDirInWorld, out vec3 lightDir, out vec3 halfVec){
+	lightDir = mat3(viewMatrix)*lightDirInWorld;
+	halfVec = normalize(normalize(lightDir) - normalize(posInView));
+	lightDir = normalize(lightDir);
+}
+
+void computePointLightingVectorsInView(in vec3 posInView, in vec3 lightPosition, out vec3 lightDir, out vec3 halfVec){
 	lightDir = vec3(viewMatrix*vec4(lightPosition, 1.0)) - posInView;
 	halfVec = normalize(lightDir - posInView);
 	lightDir = normalize(lightDir);
 }
 
 void main(void) {
-	computeLightingVectorsInView(vec3(modelViewMatrix*vec4(inPosition, 1.0)), dirLights[0], lightDirInView[0], halfVecInView[0]);
+	int i;
+	for(i=0; i<nbDirLights && i<8; ++i)
+		computeDirectionnalLightingVectorsInView(vec3(modelViewMatrix*vec4(inPosition, 1.0)), dirLights[i*2], lightDirInView[i], halfVecInView[i]);
+	for(i=0; i<nbPointLights && i+nbDirLights<8; ++i)
+		computePointLightingVectorsInView(vec3(modelViewMatrix*vec4(inPosition, 1.0)), pointLights[i*2], lightDirInView[nbDirLights+i], halfVecInView[nbDirLights+i]);
 
         // normales corrigees (en fonction de la vue)
 	varNormal = normalize(vec3(normalMatrix*vec4(inNormal,0)));
diff --git a/phongmaterial.cpp b/phongmaterial.cpp
index 5f724f9..7b474e2 100644
--- a/phongmaterial.cpp
+++ b/phongmaterial.cpp
@@ -11,7 +11,7 @@ void PhongMaterial::bindAttributes()
     if(tex != NULL)
     {
         tex->bind(TEX_ID);
-        shader->bindTexture(shader->getLocation("baseTexture"), TEX_ID);
+        shader->bindInteger(shader->getLocation("baseTexture"), TEX_ID);
     }
 }
 
diff --git a/scene.cpp b/scene.cpp
index 2831c86..7ec04cc 100644
--- a/scene.cpp
+++ b/scene.cpp
@@ -25,8 +25,8 @@ void Scene::drawAll()
         shader->bind();
         if(e->getMaterial()->requireLights())
         {
-            directionnalLights.bind(shader->getLocation("dirLights"), shader);
-            pointLights.bind(shader->getLocation("pointLights"), shader);
+            directionnalLights.bind(shader->getLocation("dirLights"), shader->getLocation("nbDirLights"), shader);
+            pointLights.bind(shader->getLocation("pointLights"), shader->getLocation("nbPointLights"), shader);
         }
         e->draw(viewMatrix, projectionMatrix);
     }
diff --git a/shader.cpp b/shader.cpp
index 9acb2ff..539c9c5 100644
--- a/shader.cpp
+++ b/shader.cpp
@@ -132,7 +132,7 @@ void Shader::bindVec3Array(GLuint location, glm::vec3* vec, int nb_elements)
     glAssert(glUniform3fv(location, nb_elements, (GLfloat*)vec));
 }
 
-void Shader::bindTexture(GLuint location, GLuint tex_id)
+void Shader::bindInteger(GLuint location, GLuint tex_id)
 {
     glAssert(glUniform1i(location, tex_id));
 }
diff --git a/shader.h b/shader.h
index 01046e0..389e785 100644
--- a/shader.h
+++ b/shader.h
@@ -25,7 +25,7 @@ public:
     void bindMatrix(GLuint location, glm::mat4 mat);
     void bindVec3(GLuint location, glm::vec3 vec);
     void bindVec3Array(GLuint location, glm::vec3* vec, int nb_elements);
-    void bindTexture(GLuint location, GLuint tex_id);
+    void bindInteger(GLuint location, GLuint tex_id);
 };
 
 #endif // SHADER_H