QtQuick2 and OpenGL 4

[Nexelen]

Hello. I'm newbie in Qt but i would like use OpenGL with QtQuick2. I tried integrate QtQuick2 and OpenGL 4.3. My test "project":https://github.com/nexelen/Qt5OpenGLStudy . But I have questions. Firts: why glClearColor dont work in initialise function? Second: why application with updates load of CPU 23%+ but if I use QWindow load of CPU 1-2%. And last question: why i must use compatibility profile(OpenGL)(I think because QtQuick2 use OpenGL 2.1)?

P.S. Sorry for my English ;)

[Nexelen]

bq. Second: why application with updates load of CPU 23%+ but if I use QWindow load of CPU 1-2%

Because QML debugging is enabled =)

[Nexelen]

Guys i have problem! Pls help me! QtQuick dont draw if text less 17 symbols. What do I do not so?

[Nexelen]

bq. QtQuick dont draw if text less 17 symbols.

Bug Qt... In latest version everything perfectly works, but there was the last question. Why glClearColor dont work in initialise function? Just work in render function, or if i use QWindow its work.