* Fix DebugDraw shaders compilation
Pull request #2317 broke compilation of the DebugDraw shaders (vs_debugdraw_fill.sc, etc)
on the Intel mesa driver. Shaders with a version lower than 130 have no
support for uvec or ivec by default on OpenGL.
This patch detects when these shaders are present and bumps the version when appropriate.
* Removed the ivecs from the patch
It seems the ivecs are infact supported on versions lower than 130 on
OpenGL.
In non-embedded shaders there is a separation between essl binaries (examples/runtime/shaders/essl)
and glsl binaries (examples/runtime/shaders/glsl). On embedded shaders there is no such separation
and by default essl shaders are being used by the OpenGL runtime. This usually doesn't cause any
issues but in the case of the debugdraw shaders, that started using uvec4, this now leads to a
runtime error. This patch fixes this by splitting the embedded shaders into essl and glsl.
As asked, this is the first part of the change.
To be able to compile the 'examples/common/debugdraw' shaders, pull
request #2362 is needed.
Compiling 'fs_texture_array.sc' with shaderc for OpenGLES fails with a syntax error,
because the matrix transpose function definitions occur before extension directives,
in this case EXT_texture_array.
When using the multview / docking feature of dear imgui (availible on the main repo in the docking branch) dear imgui will use desktop relative coordinates instead of window relative. This causing the rendering to get "offseted" if not handled correctly.
Before this change the rendering matrix wasn't used at all and this has now been changed in the vertex shader.
Notice this change is fully backwards compatible with the relative windows as well as the upper left corner will always be set to 0,0 in that case thus this change will work with both versions.
I also added some changes to skip rendering if not needed (based on the the other backend implementations for dear imgui such as the OpenGL one)
