材质

描述物体的时候，我们可以使用3种光照元素：环境光照(Ambient Lighting)、漫反射光照(Diffuse Lighting)、镜面光照(Specular Lighting)定义一个材质颜色。通过为每个元素指定一个颜色，我们已经对物体的颜色输出有了精密的控制。现在把一个镜面高光元素添加到这三个颜色里
1.片段着色器中添加材质结构体

struct Materail
{
	vec3 ambient;
	vec3 diffuse;
	vec3 specular;
	float shininess;
};

uniform Materail materail;

2.用材质的属性对之前计算的光照进行运算

vec3 lightDir = normalize(lightPos-FragPos);
float diff = max(dot(lightDir,Normal),0);
vec3 diffuse = materail.diffuse*diff*lightColor;

vec3 reflrctVec = reflect(-lightDir,Normal);
vec3 cameraVec = normalize(cameraPos-FragPos);
float specularAmount = pow(max(dot(reflrctVec,cameraVec),0),materail.shininess);
vec3 specular = materail.specular*specularAmount*lightColor;

vec3 ambient = materail.ambient*ambientColor;

  //FragColor = vec4(objColor*ambientColor,1.0f);
FragColor = vec4((diffuse+ambientColor+specular)*objColor,1.0f);

3.封装材质类

#include "Shader.h"
#include <glm/glm.hpp>
#include <glm/gtc/matrix_transform.hpp>
#include <glm/gtc/type_ptr.hpp>

class Material
{
public:
	glm::vec3 ambient;
	glm::vec3 diffuse;
	glm::vec3 specular;
	float shininess;
	Shader *shader;

	Material(Shader* _shader, glm::vec3 _ambient,glm::vec3 _diffuse,glm::vec3 _specualr,float _shininess);
	~Material();
};

#include "Material.h"



Material::Material(Shader * _shader, glm::vec3 _ambient, glm::vec3 _diffuse, glm::vec3 _specualr, float _shininess)
{
	shader = _shader;
	ambient = _ambient;
	diffuse = _diffuse;
	specular = _specualr;
	shininess = _shininess;
}

Material::~Material()
{
}

4.shader类增加设置uniform参数方法

void Shader::SetUniform3f(const char* paramNameString, glm::vec3 param)
{
	glUniform3f(glGetUniformLocation(ID, paramNameString), param.x, param.y, param.z);
}

void Shader::SetUniform1f(const char* paramNameString, float param)
{
	glUniform1f(glGetUniformLocation(ID, paramNameString), param);
}

5.传入gpu操作

Material material =  Material(&shader, glm::vec3(1.0f, 1.0f, 1.0f), glm::vec3(1.0f, 1.0f, 1.0f), glm::vec3(1.0f, 1.0f, 1.0f),32);
material.shader->SetUniform3f("material.ambient", material.ambient);
material.shader->SetUniform3f("material.diffuse", material.diffuse);
material.shader->SetUniform3f("material.specular", material.specular);
material.shader->SetUniform1f("material.shininess", material.shininess);