solvespace/src/render/rendergl.cpp
whitequark a1e18ae4a6 GlOffscreen: create color/depth renderbuffers separately.
This fixes a strange problem where GTK 2 (but not GTK 3) with NVidia
drivers would not have a depth buffer, but only during exporting
PNGs, despite the fact that normal rendering path and PNG rendering
path come through the same offscreen rendering code.
2016-08-21 19:58:45 +00:00

59 lines
2.1 KiB
C++

//-----------------------------------------------------------------------------
// Offscreen rendering in OpenGL using EGL and framebuffer objects.
//
// Copyright 2015-2016 whitequark
//-----------------------------------------------------------------------------
#ifdef __APPLE__
#include <OpenGL/GL.h>
#else
#define GL_GLEXT_PROTOTYPES
#include <GL/gl.h>
#endif
#include "solvespace.h"
void GlOffscreen::Clear() {
glDeleteRenderbuffersEXT(1, &depthRenderbuffer);
glDeleteRenderbuffersEXT(1, &colorRenderbuffer);
glDeleteFramebuffersEXT(1, &framebuffer);
*this = {};
}
bool GlOffscreen::Render(int width, int height, std::function<void()> renderFn) {
data.resize(width * height * 4);
if(framebuffer == 0)
glGenFramebuffersEXT(1, &framebuffer);
if(colorRenderbuffer == 0)
glGenRenderbuffersEXT(1, &colorRenderbuffer);
if(depthRenderbuffer == 0)
glGenRenderbuffersEXT(1, &depthRenderbuffer);
glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, framebuffer);
glBindRenderbufferEXT(GL_RENDERBUFFER_EXT, colorRenderbuffer);
glRenderbufferStorageEXT(GL_RENDERBUFFER_EXT, GL_RGBA8, width, height);
glFramebufferRenderbufferEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT,
GL_RENDERBUFFER_EXT, colorRenderbuffer);
glBindRenderbufferEXT(GL_RENDERBUFFER_EXT, depthRenderbuffer);
glRenderbufferStorageEXT(GL_RENDERBUFFER_EXT, GL_DEPTH_COMPONENT24, width, height);
glFramebufferRenderbufferEXT(GL_FRAMEBUFFER_EXT, GL_DEPTH_ATTACHMENT_EXT,
GL_RENDERBUFFER_EXT, depthRenderbuffer);
bool framebufferComplete =
glCheckFramebufferStatusEXT(GL_FRAMEBUFFER_EXT) == GL_FRAMEBUFFER_COMPLETE_EXT;
if(framebufferComplete) {
renderFn();
#if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
glReadPixels(0, 0, width, height, GL_BGRA, GL_UNSIGNED_INT_8_8_8_8_REV, &data[0]);
#else
glReadPixels(0, 0, width, height, GL_BGRA, GL_UNSIGNED_INT_8_8_8_8, &data[0]);
#endif
}
glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0);
return framebufferComplete;
}