GLSL: How to get pixel x,y,z world position?

Question

I want to adjust the colors depending on which xyz position they are in the world.

I tried this in my fragment shader:

varying vec4 verpos;

void mai         


        

Answer 1

You need to pass the World/Model matrix as a uniform to the vertex shader, and then multiply it by the vertex position and send it as a varying to the fragment shader:

/*Vertex Shader*/

layout (location = 0) in vec3 Position

uniform mat4 World;
uniform mat4 WVP;

//World FragPos
out vec4 FragPos;

void main()
{
 FragPos = World * vec4(Position, 1.0);
 gl_Position = WVP * vec4(Position, 1.0);
}

/*Fragment Shader*/

layout (location = 0) out vec4 Color;

... 

in vec4 FragPos

void main()
{
 Color = FragPos;
}