/*
    QGLView
    Ivan Pelipenko peri4ko@yandex.ru

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU Lesser 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 Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#ifndef GLFRAMEBUFFER_H
#define GLFRAMEBUFFER_H

#include <QOpenGLExtraFunctions>
#include "gltypes.h"


class GLFramebuffer : protected QOpenGLExtraFunctions
{
public:
	GLFramebuffer(int colorAttachments = 1, bool withDepth = true, GLenum colorFormat = GL_RGBA8, GLenum target = GL_TEXTURE_2D);
	virtual ~GLFramebuffer();

	GLuint id() const {return fbo;}
	GLuint colorTexture(int index = 0) const {return colors[index];}
	GLenum colorFormat() const {return color_format;}
	GLuint depthTexture() const {return tex_d;}
	GLenum target() const {return target_;}
	int width() const {return wid;}
	int height() const {return hei;}
	QSize size() const {return QSize(wid, hei);}
	QImage grab() const;

	void resize(int width, int height, bool force = false);
	void bind();
	void release();
	void setReadBuffer(int index) {glReadBuffer(GL_COLOR_ATTACHMENT0 + index);}
	void setWriteBuffer(int index);
	void setWriteBuffers(int * indeces, int count);
	void setColorFormat(GLenum format) {color_format = format; is_changed = true;}

	void copyDepthFrom(GLuint tex) {;}
	void bindColorTextures();
	void bindDepthTexture(int channel);

private:
	void deleteGLRenderbuffer(GLuint & drbo) {if (drbo != 0) glDeleteRenderbuffers(1, &drbo); drbo = 0;}
	void deleteGLFramebuffer(GLuint & fbo) {if (fbo != 0) glDeleteFramebuffers(1, &fbo); fbo = 0;}

	bool is_depth, is_changed;
	QVector<GLuint> colors;
	GLenum color_format, target_;
	GLuint fbo, drbo, tex_d;
	GLint prev_view[4], wid, hei;

};

#endif // GLFRAMEBUFFER_H