higan/extras/Shaders/old-obsolete/GameBoy.shader/gb-pass-3.vs

// This is a port of the original CG shader to the quark format
// the original shader can be found here :
// https://github.com/libretro/common-shaders/tree/master/handheld/gameboy

///////////////////////////////////////////////////////////////////////////
//                                                                       //
// Gameboy Classic Shader v0.2.2                                         //
//                                                                       //
// Copyright (C) 2013 Harlequin : unknown92835@gmail.com                 //
//                                                                       //
// This program is free software: you can redistribute it and/or modify  //
// it under the terms of the GNU General Public License as published by  //
// the Free Software Foundation, either version 3 of the License, or     //
// (at your option) any later version.                                   //
//                                                                       //
// This program is distributed in the hope that it will be useful,       //
// but WITHOUT ANY WARRANTY; without even the implied warranty of        //
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         //
// GNU General Public License for more details.                          //
//                                                                       //
// You should have received a copy of the GNU General Public License     //
// along with this program.  If not, see <http://www.gnu.org/licenses/>. //
//                                                                       //
///////////////////////////////////////////////////////////////////////////

////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//vertex shader                                                                                                                           //
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
#version 150 

in vec4 position;
in vec2 texCoord;
 
out Vertex {
   vec2 texCoord;
   vec2 lower_bound;
   vec2 upper_bound;
} vertexOut;
 
uniform vec4 targetSize;
uniform vec4 sourceSize[];

void main() {
    gl_Position = position;
    vertexOut.texCoord = texCoord;
	
  //precalculate texture parameters here so you don't have to do it for every fragment  
	vertexOut.lower_bound= vec2(0.0);
	vertexOut.upper_bound= vec2(sourceSize[0].zw * (targetSize.xy - 1.0));
}