File Viewport.cpp¶

// #####################################################################
// >>>>>>>>>>>>>>>>>>>>> BEGINNING OF LEGAL NOTICE >>>>>>>>>>>>>>>>>>>>>
//######################################################################
//
// This source file, along with its associated content, was authored by
// Andrea Settimi, Hong-Bin Yang, Naravich Chutisilp, and numerous other
// contributors. The code was originally developed at the Laboratory for
// Timber Construction (IBOIS, director: Prof. Yves Weinand) at the School of 
// Architecture, Civil and Environmental Engineering (ENAC) at the Swiss
// Federal Institute of Technology in Lausanne (EPFL) for the Doctoral
// Research "Augmented Carpentry" (PhD researcher: Andrea Settimi,
// co-director: Dr. Julien Gamerro, director: Prof. Yves Weinand).
//
// Although the entire repository is distributed under the GPL license,
// these particular source files may also be used under the terms of the
// MIT license. By accessing or using this file, you agree to the following:
//
// 1. You may reproduce, modify, and distribute this file in accordance
//    with the terms of the MIT license.
// 2. You must retain this legal notice in all copies or substantial
//    portions of this file.
// 3. This file is provided "AS IS," without any express or implied
//    warranties, including but not limited to the implied warranties of
//    merchantability and fitness for a particular purpose.
//
// If you cannot or will not comply with the above conditions, you are
// not permitted to use this file. By proceeding, you acknowledge and
// accept all terms and conditions herein.
//
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// <<<<<<<<<<<<<<<<<<<<<<< END OF LEGAL NOTICE <<<<<<<<<<<<<<<<<<<<<<<<
// #####################################################################
//


#include "Viewport.h"

namespace AIAC {
    void Viewport::Init(int w, int h) {
        m_W = w;
        m_H = h;

        glGenFramebuffers(1, &m_FrameBuffer);
        glBindFramebuffer(GL_FRAMEBUFFER, m_FrameBuffer);

        // The texture we're going to render to
        glGenTextures(1, &m_Texture);

        // "Bind" the newly created texture : all future texture functions will modify this texture
        glBindTexture(GL_TEXTURE_2D, m_Texture);

        // Give an empty image to OpenGL ( the last "0" )
        glTexImage2D(GL_TEXTURE_2D, 0,GL_RGB, m_W, m_H, 0,GL_RGB, GL_UNSIGNED_BYTE, 0);

        // Poor filtering. Needed !
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);

        // The depth buffer
        glGenRenderbuffers(1, &m_DepthBuffer);
        glBindRenderbuffer(GL_RENDERBUFFER, m_DepthBuffer);
        glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT, m_W, m_H);
        glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, m_DepthBuffer);

        // Set "renderedTexture" as our colour attachement #0
        glFramebufferTexture(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, m_Texture, 0);

        // Set the list of draw buffers.
        GLenum DrawBuffers[1] = {GL_COLOR_ATTACHMENT0};
        glDrawBuffers(1, DrawBuffers); // "1" is the size of DrawBuffers
    }

    void Viewport::Activate() {
        glBindFramebuffer(GL_FRAMEBUFFER, m_FrameBuffer);
        glViewport(0, 0, m_W, m_H);

        // "Bind" the newly created texture : all future texture functions will modify this texture
        glBindTexture(GL_TEXTURE_2D, m_Texture);

        // Give an empty image to OpenGL ( the last "0" )
        glTexImage2D(GL_TEXTURE_2D, 0,GL_RGB, m_W, m_H, 0,GL_RGB, GL_UNSIGNED_BYTE, 0);

        // Poor filtering. Needed !
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);

        // The depth buffer
        glBindRenderbuffer(GL_RENDERBUFFER, m_DepthBuffer);
        glRenderbufferStorage(GL_RENDERBUFFER, GL_DEPTH_COMPONENT, m_W, m_H);
        glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, m_DepthBuffer);

        // Set "renderedTexture" as our colour attachment #0
        glFramebufferTexture(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, m_Texture, 0);

        glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
        glEnable( GL_BLEND );
        glClearColor(1.0, 1.0, 1.0, 0.0);
        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    }
}