/** OpenGLUtility.cc file for the fluxbox compositor. */

// Copyright (c) 2011 Gediminas Liktaras (gliktaras at gmail dot com)
//
// 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.


#include "OpenGLUtility.hh"

using namespace FbCompositor;


//--- FUNCTIONS ----------------------------------------------------------------

// Converts screen coordinates to OpenGL coordinates.
void FbCompositor::toOpenGLCoords(int screen_width, int screen_height, int x, int y, int width, int height,
                                  GLfloat *x_low_return, GLfloat *x_high_return, GLfloat *y_low_return,
                                  GLfloat *y_high_return) {
    *x_low_return  = ((x * 2.0) / screen_width) - 1.0;
    *x_high_return = (((x + width) * 2.0) / screen_width) - 1.0;
    *y_low_return  = 1.0 - ((y * 2.0) / screen_height);
    *y_high_return = 1.0 - (((y + height) * 2.0) / screen_height);
}

// Converts screen coordinates to OpenGL coordinates. */
void FbCompositor::toOpenGLCoords(int screen_width, int screen_height, XRectangle rect,
                                  GLfloat *x_low_return, GLfloat *x_high_return, GLfloat *y_low_return,
                                  GLfloat *y_high_return) {
    toOpenGLCoords(screen_width, screen_height, rect.x, rect.y, rect.width, rect.height,
                        x_low_return, x_high_return, y_low_return, y_high_return);
}