shader

shader.c

uniform vec3 glowColor;
uniform float coeficient;
uniform float cutoff;
uniform float power;

varying vec3 vVertexNormal;
varying vec3 vVertexWorldPosition;

void main(){
 vec3 worldCameraToVertex = vVertexWorldPosition - cameraPosition;
 vec3 viewCameraToVertex = (viewMatrix * vec4(worldCameraToVertex, 0.0)).xyz;
 viewCameraToVertex = normalize(viewCameraToVertex);
 float cosTheta = dot(vVertexNormal, viewCameraToVertex);
 float intensity = pow(coeficient + cosTheta, power);
 // Attempt to stop drawing of the shader when looking up
 if (cosTheta > cutoff) {
   intensity = 0.0;
 }
 gl_FragColor= vec4(glowColor, intensity);
}