atmosphere_vs.glsl

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/**
 * @file
 * @brief Atmosphere vertex shader
 */

out_qualifier vec2 tex;

out_qualifier vec4 ambientLight;
out_qualifier vec4 diffuseLight;
out_qualifier vec4 specularLight;

out_qualifier vec3 lightVec;
out_qualifier vec3 eyeVec;

uniform vec2 UVSCALE;

void main() {
   gl_Position = ftransform();

   tex = gl_MultiTexCoord0.xy * UVSCALE;

   vec4 lightPos = gl_LightSource[0].position;
   ambientLight = gl_LightSource[0].ambient;
   diffuseLight = gl_LightSource[0].diffuse;
   specularLight = gl_LightSource[0].specular;

   vec3 t, b, n;
   n = normalize(gl_NormalMatrix * gl_Normal);
   t = normalize(cross(n, vec3(1.0, 0.0, 0.0)));
   b = normalize(cross(t, n));

   lightVec.x = dot(lightPos.rgb, t);
   lightVec.y = dot(lightPos.rgb, b);
   lightVec.z = dot(lightPos.rgb, n);

   /* estimate view vector (orthographic projection means we don't really have one) */
   vec4 view = vec4(0.0, 0.0, 100.0, 1.0);
   eyeVec.x = dot(view.xyz, t);
   eyeVec.y = dot(view.xyz, b);
   eyeVec.z = dot(view.xyz, n);
}