qtk/resources/shaders/vertex/phong.vert

39 lines
1.1 KiB
GLSL

#version 330
layout(location = 0) in vec3 aPosition;
layout(location = 1) in vec3 aNormal;
out vec3 vPosition;
out vec3 vNormal;
// Model View Projection matrix found by P * V * M
struct MVP {
mat4 model;
mat4 view;
mat4 projection;
// Additional uniform to allow CPU to provide mat3(transpose(inverse(uModel)))
// + Makes a big difference in quality of diffuse shading
// + QMatrix4x4.normalMatrix() returns a mat3 that can be used as a uniform
mat3 normalMatrix;
};
uniform MVP uMVP;
vec4 VertexPosition(in MVP mvp, in vec3 position)
{
return mvp.projection * mvp.view * mvp.model * vec4(position, 1.0f);
}
void main()
{
// Find normals, pass to fragment shader
vNormal = uMVP.normalMatrix * aNormal;
// vNormal = aNormal; // This is possible without the additional uniform
// Or you could find this on the GPU using the uModel matrix
// vNormal = mat3(transpose(inverse(uModel))) * aNormal;
// Set the vertex position to pass to fragment shader using only model matrix
vPosition = vec3(uMVP.model * vec4(aPosition, 1.0f));
// Set vertex gl_Position using MVP matrix
gl_Position = VertexPosition(uMVP, aPosition);
}