kwin/libkwineffects/kwinglutils_funcs.cpp
Martin Gräßlin d7fa827644 Pass function ptr to resolve glFunctions to initGL
Summary:
KWin still resolves some OpenGL function pointers. For that it needs to
use either eglGetProcAddress or glxGetProcAddress. With other words the
method to resolve needs to know whether it is egl or glx and needs both
a dependency to egl and glx. Especially the dependency to glx is ugly as
that pulls in XLib into our library.

The way so far was to pass an enum value to the initGL method to know
whether it's EGL or GLX. With this change the enum value is removed and
replaced by a function pointer to resolve the methods.

This simplifies the resolve code and allows to completely remove the glx
variant we still had in the library. Thus kwinglutils library is now glx
and XLib free.

Test Plan: nested KWin with OpenGL/EGL still works

Reviewers: #kwin, #plasma_on_wayland

Subscribers: plasma-devel, kwin

Tags: #plasma_on_wayland, #kwin

Differential Revision: https://phabricator.kde.org/D3336
2016-11-16 17:59:26 +01:00

106 lines
4 KiB
C++

/********************************************************************
KWin - the KDE window manager
This file is part of the KDE project.
Copyright (C) 2007 Rivo Laks <rivolaks@hot.ee>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*********************************************************************/
#include "kwinglutils.h"
#include "kwinglplatform.h"
// Resolves given function, using getProcAddress
// Useful when functionality is defined in an extension with a different name
#define GL_RESOLVE_WITH_EXT( function, symbolName ) \
function = (function ## _func)resolveFunction( #symbolName );
namespace KWin
{
static GLenum GetGraphicsResetStatus();
static void ReadnPixels(GLint x, GLint y, GLsizei width, GLsizei height, GLenum format,
GLenum type, GLsizei bufSize, GLvoid *data);
static void GetnUniformfv(GLuint program, GLint location, GLsizei bufSize, GLfloat *params);
// GL_ARB_robustness / GL_EXT_robustness
glGetGraphicsResetStatus_func glGetGraphicsResetStatus;
glReadnPixels_func glReadnPixels;
glGetnUniformfv_func glGetnUniformfv;
void eglResolveFunctions()
{
}
void glResolveFunctions(std::function<resolveFuncPtr(const char*)> resolveFunction)
{
const bool haveArbRobustness = hasGLExtension(QByteArrayLiteral("GL_ARB_robustness"));
const bool haveExtRobustness = hasGLExtension(QByteArrayLiteral("GL_EXT_robustness"));
bool robustContext = false;
if (GLPlatform::instance()->isGLES()) {
if (haveExtRobustness) {
GLint value = 0;
glGetIntegerv(GL_CONTEXT_ROBUST_ACCESS_EXT, &value);
robustContext = (value != 0);
}
} else {
if (haveArbRobustness) {
if (hasGLVersion(3, 0)) {
GLint value = 0;
glGetIntegerv(GL_CONTEXT_FLAGS, &value);
if (value & GL_CONTEXT_FLAG_ROBUST_ACCESS_BIT_ARB) {
robustContext = true;
}
} else {
robustContext = true;
}
}
}
if (robustContext && haveArbRobustness) {
// See http://www.opengl.org/registry/specs/ARB/robustness.txt
GL_RESOLVE_WITH_EXT(glGetGraphicsResetStatus, glGetGraphicsResetStatusARB);
GL_RESOLVE_WITH_EXT(glReadnPixels, glReadnPixelsARB);
GL_RESOLVE_WITH_EXT(glGetnUniformfv, glGetnUniformfvARB);
} else if (robustContext && haveExtRobustness) {
// See http://www.khronos.org/registry/gles/extensions/EXT/EXT_robustness.txt
glGetGraphicsResetStatus = (glGetGraphicsResetStatus_func) resolveFunction("glGetGraphicsResetStatusEXT");
glReadnPixels = (glReadnPixels_func) resolveFunction("glReadnPixelsEXT");
glGetnUniformfv = (glGetnUniformfv_func) resolveFunction("glGetnUniformfvEXT");
} else {
glGetGraphicsResetStatus = KWin::GetGraphicsResetStatus;
glReadnPixels = KWin::ReadnPixels;
glGetnUniformfv = KWin::GetnUniformfv;
}
}
static GLenum GetGraphicsResetStatus()
{
return GL_NO_ERROR;
}
static void ReadnPixels(GLint x, GLint y, GLsizei width, GLsizei height, GLenum format,
GLenum type, GLsizei bufSize, GLvoid *data)
{
Q_UNUSED(bufSize)
glReadPixels(x, y, width, height, format, type, data);
}
static void GetnUniformfv(GLuint program, GLint location, GLsizei bufSize, GLfloat *params)
{
Q_UNUSED(bufSize)
glGetUniformfv(program, location, params);
}
} // namespace