From 8de75c7c47c9701caab299b801abd4d27e87c342 Mon Sep 17 00:00:00 2001
From: Martin Felis <martin@fysx.org>
Date: Sun, 11 Mar 2018 14:16:23 +0100
Subject: [PATCH] Added specular highlights

---
 data/shaders/fs_default.glsl | 15 +++++++++++++--
 data/shaders/vs_default.glsl |  9 +++++++--
 src/modules/RenderModule.cc  | 12 +++++++-----
 3 files changed, 27 insertions(+), 9 deletions(-)

diff --git a/data/shaders/fs_default.glsl b/data/shaders/fs_default.glsl
index c512d00..e7c4656 100644
--- a/data/shaders/fs_default.glsl
+++ b/data/shaders/fs_default.glsl
@@ -2,21 +2,32 @@
 
 uniform vec4 uColor;
 uniform vec3 uLightDirection;
+uniform vec3 uViewPosition;
 
 smooth in vec4 ioFragColor;
 in vec3 ioNormal;
+in vec3 ioFragPosition;
 
 out vec4 outColor;
 
 void main() {
+	// ambient lighting
 	float ambient_strength = 0.1;
-
 	vec4 ambient = ambient_strength * ioFragColor;
 
+	// diffuse lighting
 	vec3 norm = normalize(ioNormal);
 	vec3 light_dir = normalize(uLightDirection);
 	float diff = max(dot(norm, light_dir), 0.0);
 	vec4 diffuse = diff * ioFragColor;
 
-	outColor = ambient + diffuse;
+	// specular lighting
+	vec3 view_dir = normalize(uViewPosition - ioFragPosition);
+	vec3 reflect_dir = reflect(-light_dir, norm);
+
+	float specular_strength = 0.5;
+	float spec = pow(max(dot(view_dir, reflect_dir), 0.0), 32);
+	vec4 specular = specular_strength * spec * vec4(1.0, 1.0, 1.0, 1.0);
+
+	outColor = ambient + diffuse + specular;
 }
diff --git a/data/shaders/vs_default.glsl b/data/shaders/vs_default.glsl
index 179efcc..29d3b7f 100644
--- a/data/shaders/vs_default.glsl
+++ b/data/shaders/vs_default.glsl
@@ -6,14 +6,19 @@ in vec3 inNormal;
 in vec2 inUV;
 in vec4 inColor;
 
-uniform mat4 uModelViewProj;
+uniform mat4 uModelMatrix;
+uniform mat4 uViewMatrix;
+uniform mat4 uProjectionMatrix;
 uniform vec3 uLightDirection;
+uniform vec3 uViewPosition;
 
 smooth out vec4 ioFragColor;
 out vec3 ioNormal;
+out vec3 ioFragPosition;
 
 void main() {
-	gl_Position = uModelViewProj * inCoord;
+	gl_Position = uProjectionMatrix * uViewMatrix * uModelMatrix * inCoord;
 	ioFragColor = inColor;
 	ioNormal = inNormal;
+	ioFragPosition = (uModelMatrix * inCoord).xyz;
 }
diff --git a/src/modules/RenderModule.cc b/src/modules/RenderModule.cc
index 878f4d7..1ed1724 100644
--- a/src/modules/RenderModule.cc
+++ b/src/modules/RenderModule.cc
@@ -465,13 +465,15 @@ void Renderer::RenderGl() {
 	// Unit cube
 	glUseProgram(mDefaultProgram.mProgramId);
 
-	model_view_projection = 
-		TranslateMat44(3.0f, 0.0f, 1.0f)
-		* mCamera.mViewMatrix
-		* mCamera.mProjectionMatrix;
-  mDefaultProgram.SetMat44("uModelViewProj", model_view_projection);
+	model_matrix = TranslateMat44(3.0f, 0.0f, 1.0f);
+
+	mDefaultProgram.SetMat44("uModelMatrix", model_matrix);
+	mDefaultProgram.SetMat44("uViewMatrix", mCamera.mViewMatrix);
+	mDefaultProgram.SetMat44("uProjectionMatrix", mCamera.mProjectionMatrix);
+
   mDefaultProgram.SetVec4("uColor", Vector4f (1.0f, 0.0f, 0.0f, 1.0f));
 	mDefaultProgram.SetVec3("uLightDirection", mLight.mDirection);
+	mDefaultProgram.SetVec3("uViewPosition", mCamera.mEye);
 	gVertexArray.Bind();
 	gUnitCubeMesh.Draw(GL_TRIANGLES);