点光源和blin

main.cpp

@@ -96,8 +96,8 @@ INT WINAPI WinMain(_In_ HINSTANCE hInstance, _In_opt_ HINSTANCE hPrevInstance, _
 	float ambientLightColor[] = {0.4f,0.4f,0.4f,1.0f};
 	float ambientMaterial[] = { 0.2f,0.2f,0.2f,1.0f };
 	float diffuseLightColor[] = { 1.0f,1.0f,1.0f,1.0f };
-	float diffuseMaterial[] = { 0.8f,0.8f,0.8f,1.0f };
-	float lightPos[] = {1.0f,1.0f,0.0f,0.0f};
+	float diffuseMaterial[] = { 0.6f,0.6f,0.6f,1.0f };
+	float lightPos[] = {3.0f,3.0f,0.0f,1.0f};
 	float specularLightColor[] = { 1.0f,1.0f,1.0f,1.0f };
 	float specularMaterial[] = { 1.0f,1.0f,1.0f,1.0f };
 	float eyePos[] = { 0.0f,0.0f,0.0f };

res/shader/test.fs

@@ -17,20 +17,35 @@ void main()
 	vec4 ambientColor = U_AmbientLightColor * U_AmbientMaterial;
 
 	//diffuse
-	vec3 L = normalize(U_LightPos.xyz);
+	vec3 L = vec3(0.0);
+	float distance = 0.0;
+	float attenuation = 1.0;
+
+	//light attribute
+	float constantFactor=0.5;
+	float linearFactor=0.3;
+	float expFactor=0.1;
+
+	if(U_LightPos.w==0.0){
+		//这是方向光
+		L = normalize(U_LightPos.xyz);
+	} else {
+		//这是点光源
+		//model point -> light pos
+		L = normalize(U_LightPos.xyz - V_WorldPos);
+		distance = length(U_LightPos.xyz - V_WorldPos);
+		attenuation = 1.0 / (constantFactor + linearFactor * distance + expFactor * distance * distance);
+	}
 	vec3 N = normalize(V_Normal);
-	float diffuseIntensity = max(0.0, dot(L,N));
-	vec4 diffuseColor = U_DiffuseLightColor * U_DiffuseMaterial * diffuseIntensity;
 
-	//specular
-	//vec3 reflectDir = normalize(reflect(-L,N));//-L是入射光向量，通过reflect函数求到反射光方向
-	//vec3 viewDir = normalize(U_EyePos - V_WorldPos);
-	//vec4 specularColor = U_SpecularLightColor * U_SpecularMaterial * pow(max(0.0, dot(viewDir,reflectDir)), 64.0);
+
+	float diffuseIntensity = max(0.0, dot(L,N));
+	vec4 diffuseColor = U_DiffuseLightColor * U_DiffuseMaterial * diffuseIntensity * attenuation;
 
 	//specular blin
 	vec3 viewDir = normalize(U_EyePos - V_WorldPos);
 	vec3 M = normalize(L + viewDir);
-	vec4 specularColor = U_SpecularLightColor * U_SpecularMaterial * pow(max(0.0, dot(M,N)), 64.0);
+	vec4 specularColor = U_SpecularLightColor * U_SpecularMaterial * pow(max(0.0, dot(M,N)), 64.0)  * attenuation;
 
 
 	gl_FragColor = ambientColor + diffuseColor + specularColor;