QT+OpenGL反射与折射
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反射
反射这个属性表现为物体(或者物体的一部分)反射它周围的环境，即根据观察者的视角，物体的颜色或多或少等于他的环境。
最终的反射向量将会作为索引/采样立方体贴图的方向向量，返回颜色的值。
关键代码：
shader.vert
#version 330 core layout (location = 0) in vec3 aPos; layout (location = 1) in vec3 aNormal; layout (location = 2) in vec2 aTexCoords; out vec3 Normal; out vec3 FragPos; out vec2 TexCoords; uniform mat4 model; uniform mat4 view; uniform mat4 projection; void main() { TexCoords=aTexCoords; Normal = mat3(transpose(inverse(model))) * aNormal; FragPos=vec3(model * vec4(aPos,1.0)); gl_Position = projection * view * model * vec4(aPos, 1.0); }
shader.frag
#version 330 core struct Material { sampler2D texture_diffuse1; sampler2D texture_specular1; float shininess; }; struct Light { vec3 direction; vec3 ambient; vec3 diffuse; vec3 specular; }; uniform Light light; uniform Material material; out vec4 FragColor; in vec2 TexCoords; in vec3 Normal; in vec3 FragPos; uniform vec3 viewPos; void main() { vec3 diffuseTexColor=vec3(texture(material.texture_diffuse1,TexCoords)); vec3 specularTexColor=vec3(texture(material.texture_specular1,TexCoords)); // ambient vec3 ambient = diffuseTexColor*light.ambient; // diffuse vec3 norm = normalize(Normal); vec3 lightDir = normalize(-light.direction); float diff = max(dot(norm, lightDir), 0.0); vec3 diffuse = diff *diffuseTexColor*light.diffuse; // specular vec3 viewDir = normalize(viewPos - FragPos); vec3 reflectDir = reflect(-lightDir, norm); float spec = pow(max(dot(viewDir, reflectDir), 0.0), material.shininess); vec3 specular = spec*specularTexColor*light.specular; vec3 result = (ambient + diffuse + specular); FragColor = vec4(result, 1.0); }
reflection.vert
#version 330 core layout (location = 0) in vec3 aPos; layout (location = 1) in vec3 aNormal; out vec3 Normal; out vec3 Position; uniform mat4 model; uniform mat4 view; uniform mat4 projection; void main() { Normal = mat3(transpose(inverse(model))) * aNormal; Position = vec3(model * vec4(aPos, 1.0)); gl_Position = projection * view * vec4(Position, 1.0); }
reflection.frag
#version 330 core out vec4 FragColor; in vec3 Normal; in vec3 Position; uniform vec3 viewPos; uniform samplerCube skybox; void main() { vec3 I = normalize(Position - viewPos); vec3 R = reflect(I, normalize(Normal)); FragColor = vec4(texture(skybox, R).rgb, 1.0); }
折射
折射是光线由于传播介质的改变而产生的方向变化。折射是通过斯涅尔定律来描述的。
折射可以使用GLSL的内建refract函数来轻松实现，他需要一个法向量、一个观察方向和两个材质之间的折射率。
这里使用反射的shader。
主要代码：
reflection.frag
void main() { float ratio = 1.00/1.52; vec3 I = normalize(Position - cameraPos); vec3 R = refract(I, normalize(Normal), ratio); FragColor = vec4(texture(skybox, R).rgb, 1.0); }
