GL_PRIMITIVE_RESTART_FIXED_INDEX not works on Android's OpenGL ES

[PowerNow]

Hi, I want to render multiple objects based on Qt 5.12/Qml/OpenGL ES 3.1+ via GL_TRIANGLE_STRIP and splitted by 'Primitive Restart'. I tested it on Win10 and everything works fine. The problem now is that

m_func->glEnable(GL_PRIMITIVE_RESTART_FIXED_INDEX);

is only accepted from usual OpenGL. The reason is that Qt's glEnable() supports only OpenGL ES 2.0 and GL_PRIMITIVE_RESTART_FIXED_INDEX is only up from OpenGL ES 3.x.

So does maybe someone know how to

1. use consequently in Qt OpenGL ES 3.x and not extraFunctions()?
2. use 'Primitive Restart' with Qt?

Thanks in advance...

[SGaist]

Hi,

Please take a look at the OpenGL ES 3 example to see how to enable a different version of OpenGL.

[PowerNow]

@SGaist Thxs, but as I mentioned in point 1. I already use

m_func = QOpenGLContext::currentContext()->extraFunctions();

The problem is that GL_PRIMITIVE_RESTART_FIXED_INDEX is unknown using with

m_func->glEnable(...);

for OpenGL ES. glEnable() is from QOpenGLFunctions and QOpenGLExtraFunctions is only inherited from it.

[SGaist]

I am not sure I am following you as QOpenGLExtraFunctions already support OpenGL ES 3.

[PowerNow]

@SGaist Yes QOpenGLExtraFunctions supports OpenGL ES 3, but the function glEnable() contains to QOpenGLFunctions and this supports only OpenGL ES 2.

"The QOpenGLFunctions class provides cross-platform access to the OpenGL ES 2.0 API"

And GL_PRIMITIVE_RESTART_FIXED_INDEX was only introduced with OpenGL ES 3.x.

So my question is how can I use in Qt with OpenGL ES GL_PRIMITIVE_RESTART_FIXED_INDEX to render multiple objects using only one draw command glDrawElements()?

[SGaist]

@PowerNow said in GL_PRIMITIVE_RESTART_FIXED_INDEX not works on Android's OpenGL ES:

GL_PRIMITIVE_RESTART_FIXED_INDEX

While the primitive name itself seems to not be defined, what you can do is:

#ifndef GL_PRIMITIVE_RESTART_FIXED_INDEX
#define GL_PRIMITIVE_RESTART_FIXED_INDEX  0x8D69
#endif

Note that this is taken from within Qt's source code.

Does that work ?

[PowerNow]

@SGaist Yeah, this works, thxs! But also if GL_PRIMITIVE_RESTART_FIXED_INDEX is defined how can it work with glEnable() from QOpenGLFunctions? Should be there not an overwritten member function glEnable() of QOpenGLExtraFunctions?

https://bugreports.qt.io/browse/QTBUG-83034

[SGaist]

Because you requested the adequate context version.