qt5base-lts/util
Sean Harmer 9eb9bd703b OpenGL: Add code generator for OpenGL enabler classes
This patch provides a code generator that can be executed offline
to generate a few classes for enhancing Qt's support for OpenGL.
The generated code effectively provides all the benefits of GLEW
in its multi-context form but for all platforms and even for ES2.

The code generator takes as input the official Khronos gl.spec
specification and gl.tm typemap files. These provide all of the
information required to create the OpenGL Desktop related classes.
The classes for ES2 are hand-crafted as no similar spec files have
been published.

The generated code supports all OpenGL extensions listed in the
Khronos registry for both Desktop OpenGL and ES 2.

There is a helper factory class generated which are used by
QOpenGLContext::versionFunctions().

This allows code like the following to be written:

QOpenGLFunctions_3_3_Core* m_funcs = 0;
m_funcs = m_context->versionFunctions<QOpenGLFunctions_3_3_Core>();
if (!m_funcs) {
    qWarning() << "Could not obtain required OpenGL context version";
    exit(1);
}

if (!m_funcs->initializeOpenGLFunctions()) {
    qWarning() << "Failed to resolve entry points";
    exit(2);
}

// Get an extension object
QOpenGLExtension_ARB_draw_buffers* ext = 0;
if (m_context->hasExtension("GL_ARB_draw_buffers")) {
    ext = new QOpenGLExtension_ARB_draw_buffers();
    ext->initializeOpenGLFunctions(m_context);
}

Such usage will allow much easier and rigorous use of features in
modern OpenGL and extensions both in Qt itself and by users of Qt.

Follow-up patches will import the generated files and then use
these to reinstate OpenGL geometry shaders, add tessellation
shaders, and other OpenGL constructs.

Change-Id: Id0172e8aa1fd57eb4e6979a96d10fb5a34826426
Reviewed-by: Samuel Rødal <samuel.rodal@digia.com>
Reviewed-by: James Turner <james.turner@kdab.com>
2013-02-25 17:22:28 +01:00
..
accessibilityinspector Update copyright year in Digia's license headers 2013-01-18 09:07:35 +01:00
aglfn Update copyright year in Digia's license headers 2013-01-18 09:07:35 +01:00
corelib/qurl-generateTLDs QUrl effective TLDs: update table and split into chunks of 64K 2013-02-09 10:12:44 +01:00
glgen OpenGL: Add code generator for OpenGL enabler classes 2013-02-25 17:22:28 +01:00
harfbuzz Initial import from the monolithic Qt. 2011-04-27 12:05:43 +02:00
integrity Initial import from the monolithic Qt. 2011-04-27 12:05:43 +02:00
lexgen Nokia -> Qt Project 2013-02-05 20:53:57 +01:00
local_database Fix minor typos in docs, printed messages & comments 2013-01-28 18:12:41 +01:00
plugintest Update copyright year in Digia's license headers 2013-01-18 09:07:35 +01:00
scripts Update copyright year in Digia's license headers 2013-01-18 09:07:35 +01:00
unicode Merge remote-tracking branch 'origin/stable' into dev 2013-01-22 18:40:13 +01:00
xkbdatagen Update copyright year in Digia's license headers 2013-01-18 09:07:35 +01:00