Phong光照

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完整的程序
https://github.com/WaldenPonder/opengl-test/tree/master/t005

顶点着色器

#version 330 core
layout (location = 0) in vec3 aPosition;
layout (location = 1) in vec2 aCoor;
layout (location = 1) in vec3 aNormal;

uniform mat4 uModel;
uniform mat4 uView;
uniform mat4 uProjection;

out vec2 vTexCoor;
out vec3 vNormal;
out vec3 vPos;

void main()
{
    gl_Position = uProjection * uView * uModel * vec4(aPosition.x, aPosition.y, aPosition.z, 1.0);
    //gl_Position = model * vec4(aPosition.x, aPosition.y, aPosition.z, 1.0);
    vTexCoor = vec2(aCoor.x, aCoor.y);
    vNormal = mat3(transpose(inverse(uModel))) * aNormal;
    vPos = (uModel * vec4(aPosition, 1.0f)).xyz;
}

片段着色器

#version 330 core

uniform sampler2D uSAMP;
uniform vec3  uLightPos;
uniform vec3  uViewPos;
uniform vec3  uLightColor;

out vec4 fColor;

in vec2 vTexCoor;
in vec3 vNormal;
in vec3 vPos;

void main()
{
    //vec4 color = texture(uSAMP, vTexCoor);
    vec4 color = vec4(0.3, 0.3, 0.6, 1);

    //ambient
    float factor = 0.4f;
    vec3 ambient = factor *  uLightColor;

    //diffuse
    vec3 n = normalize(vNormal);
    vec3 lightDir = normalize(uLightPos - vPos);
    float factor2 = max(dot(n, lightDir), 0);
    vec3 diffuse = factor2 * uLightColor;

    //specular
    float strength = 0.6f;
    vec3 viewDir = normalize(uViewPos - vPos);
    vec3 reflectDir = reflect(-lightDir, n);
    float factor4 =pow(max(dot(reflectDir, viewDir), 0), 128);

    vec3 specular = factor4 * strength * uLightColor;


    vec3 result = (ambient + diffuse + specular) * color.xyz;

    //fColor = color;
    fColor = vec4(result, 1.0);
}