love2d.love/src/modules/graphics/opengl/Quad.cpp

/**
 * Copyright (c) 2006-2012 LOVE Development Team
 *
 * This software is provided 'as-is', without any express or implied
 * warranty.  In no event will the authors be held liable for any damages
 * arising from the use of this software.
 *
 * Permission is granted to anyone to use this software for any purpose,
 * including commercial applications, and to alter it and redistribute it
 * freely, subject to the following restrictions:
 *
 * 1. The origin of this software must not be misrepresented; you must not
 *    claim that you wrote the original software. If you use this software
 *    in a product, an acknowledgment in the product documentation would be
 *    appreciated but is not required.
 * 2. Altered source versions must be plainly marked as such, and must not be
 *    misrepresented as being the original software.
 * 3. This notice may not be removed or altered from any source distribution.
 **/

#include "Quad.h"
#include "common/Matrix.h"

// OpenGL
#include "OpenGL.h"

// STD
#include <cstring> // For memcpy

namespace love
{
namespace graphics
{
namespace opengl
{

Quad::Quad(const Viewport &v, float sw, float sh)
	: sw(sw)
	, sh(sh)
{
	memset(vertices, 255, sizeof(vertex)*NUM_VERTICES);
	refresh(v, sw, sh);
}

Quad::~Quad()
{
}

void Quad::refresh(const Viewport &v, float sw, float sh)
{
	if (!GLEE_ARB_texture_non_power_of_two)
	{
		sw = next_p2(sw);
		sh = next_p2(sh);
	}
	viewport = v;

	vertices[0].x = 0;
	vertices[0].y = 0;
	vertices[1].x = 0;
	vertices[1].y = v.h;
	vertices[2].x = v.w;
	vertices[2].y = v.h;
	vertices[3].x = v.w;
	vertices[3].y = 0;

	vertices[0].s = v.x/sw;
	vertices[0].t = v.y/sh;
	vertices[1].s = v.x/sw;
	vertices[1].t = (v.y+v.h)/sh;
	vertices[2].s = (v.x+v.w)/sw;
	vertices[2].t = (v.y+v.h)/sh;
	vertices[3].s = (v.x+v.w)/sw;
	vertices[3].t = v.y/sh;
}

void Quad::setViewport(const Quad::Viewport &v)
{
	refresh(v, sw, sh);
}

Quad::Viewport Quad::getViewport() const
{
	return viewport;
}

void Quad::flip(bool x, bool y)
{
	vertex temp[4];
	if (x)
	{
		memcpy(temp, vertices, sizeof(vertex)*NUM_VERTICES);
		vertices[0].s = temp[3].s;
		vertices[0].t = temp[3].t;
		vertices[1].s = temp[2].s;
		vertices[1].t = temp[2].t;
		vertices[2].s = temp[1].s;
		vertices[2].t = temp[1].t;
		vertices[3].s = temp[0].s;
		vertices[3].t = temp[0].t;
	}
	if (y)
	{
		memcpy(temp, vertices, sizeof(vertex)*NUM_VERTICES);
		vertices[0].s = temp[1].s;
		vertices[0].t = temp[1].t;
		vertices[1].s = temp[0].s;
		vertices[1].t = temp[0].t;
		vertices[2].s = temp[3].s;
		vertices[2].t = temp[3].t;
		vertices[3].s = temp[2].s;
		vertices[3].t = temp[2].t;
	}
}

const vertex *Quad::getVertices() const
{
	return vertices;
}

} // opengl
} // graphics
} // love