GLSL

#if COMPILING_VS

uniform TransformBlock {
    mat4 Projection;
    mat4 View;
} Transform;

uniform MaterialBlock {
    vec4 Color;
} Material;

out Vertex {
    vec2 Position;
    vec2 TexCoord;
    vec4 Color;
} Out;

void main()
{
    Out.Position = gl_Vertex.xy;
    Out.TexCoord = gl_MultiTexCoord0.st;
    Out.Color = Material.Color;
    gl_Position = Transform.Projection * Transform.View * gl_Vertex;
}

#elif COMPILING_FS

in Vertex {
    vec2 Position;
    vec2 TexCoord;
    vec4 Color;
} In;

/*
uniform unsigned int LightCount;
uniform Lights {
    vec2 Pos;
    vec2 Dir;
    vec2 Threshold;
    vec3 Color;
} Light[];
*/

void main()
{
    vec2 LightPos = vec2(0, 350);
    vec2 LightDir = vec2(0, -1);
    float Threshold1 = cos(3.1415 * 0.20);
    float Threshold2 = cos(3.1415 * 0.21);
    vec3 LightColor = vec3(1.0, 0.2, 0.8);
    float Attenuation = 0.2;

    vec2 L = In.Position - LightPos;
    float SqrDistance = dot(L, L);
    vec2 LightVec = normalize(L);
    float CosPhi = dot(LightDir, LightVec);
    float Brightness = smoothstep(Threshold2, Threshold1, CosPhi) / (1 + SqrDistance/75000);
    vec3 Color = (Attenuation + (1 - Attenuation) * Brightness * LightColor) * In.Color.rgb;
    gl_FragColor = vec4(Color, In.Color.a);
}

#endif