[fixed]MacOS 10.15 only rendering to quarter of window

[bridgeco]

Following the release of MacOS Catalina, I had a problem where the Irrlicht was only rendering to the lower left quarter of the window. The same problem appeared at the same time for a number of other 3d engines (see https://github.com/panda3d/panda3d/issues/794 which also links to the same problem in SDL and Godot).

The problem is related to the scaling applied on 'HiDPI' screens. Prior to Catalina (10.15), MacOS by applied scaling by default to OpenGL applications so applications did not need to be HiDPI aware, but this default changed in 10.15.

To avoid the problem, you need to set setWantsBestResolutionOpenGLSurface:NO for the OpenGL context.

Following the approach taken in the other engines, in CIrrDeviceOSX.mm, the fix is to change the lines

Code: Select all

 
                if (Window)
                    [(NSOpenGLContext*)ContextManager->getContext().OpenGLOSX.Context setView:[Window contentView]];
                else
                    [(NSOpenGLContext*)ContextManager->getContext().OpenGLOSX.Context setView:(NSView*)CreationParams.WindowId];
 

to

Code: Select all

 
                if (Window) {
                    [[Window contentView] setWantsBestResolutionOpenGLSurface:NO];
                    [(NSOpenGLContext*)ContextManager->getContext().OpenGLOSX.Context setView:[Window contentView]];
                } else {
                    [(NSView*)CreationParams.WindowId setWantsBestResolutionOpenGLSurface:NO];
                    [(NSOpenGLContext*)ContextManager->getContext().OpenGLOSX.Context setView:(NSView*)CreationParams.WindowId];
                }
 

Theoretically, it might be better to re-code everything that handles dimensions to be HiDPI aware, but that's certainly not something I know enough to do!

[CuteAlien]

Yeah, also not going to re-code. But applied this to svn trunk [r6132], thanks!