/*****************************************************************************************
 *                                                                                       *
 * OpenSpace                                                                             *
 *                                                                                       *
 * Copyright (c) 2014-2016                                                               *
 *                                                                                       *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of this  *
 * software and associated documentation files (the "Software"), to deal in the Software *
 * without restriction, including without limitation the rights to use, copy, modify,    *
 * merge, publish, distribute, sublicense, and/or sell copies of the Software, and to    *
 * permit persons to whom the Software is furnished to do so, subject to the following   *
 * conditions:                                                                           *
 *                                                                                       *
 * The above copyright notice and this permission notice shall be included in all copies *
 * or substantial portions of the Software.                                              *
 *                                                                                       *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,   *
 * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A         *
 * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT    *
 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF  *
 * CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE  *
 * OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                                         *
 ****************************************************************************************/

#version __CONTEXT__

uniform sampler2D projectTexture;
uniform sampler2D currentTexture;

uniform mat4 ProjectorMatrix;
uniform mat4 ModelTransform;
uniform vec2 _scaling;
uniform vec3 boresight;


in vec4 vs_position;
in vec4 ProjTexCoord;
in vec2 vs_uv;
in vec4 vs_normal;

out vec4 color;

#include "PowerScaling/powerScaling_vs.hglsl"

bool inRange(float x, float a, float b) {
    return (x >= a && x <= b);
} 

void main() {
  vec2 uv = vec2(0.5,0.5)*vs_uv+vec2(0.5,0.5);

  vec3 n = normalize(vs_normal.xyz);
  vec4 projected = ProjTexCoord;

  //normalize
  projected.x /= projected.w;
  projected.y /= projected.w;
  //invert gl coordinates
  projected.x = 1 - projected.x;
  projected.y = 1 - projected.y; 
  
  if((inRange(projected.x, 0, 1) && inRange(projected.y, 0, 1)) && (dot(n, boresight) < 0)) {
        color = texture(projectTexture, projected.xy);
  } else {
        color = texture(currentTexture, uv);
  }

}