/*
    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 "gltypes.h"

#include <QOpenGLExtraFunctions>


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