Double sized icons in UI? I want to implement bigger buttons, with icons at it. Preferable double size of what we currently have. I can scale the button height by row.scale_y . But the size of icons is hardcoded to 16 pixels. Can be found in the source\blender\editors\include\UI_interface_icons.h

But you can scale the UI with the dpi settings in the user preferences. And then the icons becomes bigger with the rest of the UI. Question is, is there a Python way to scale icons bigger for just one UI element?

And in case not, is there another way to implement buttons with bigger icons by Python? I would even be happy about hints how to do this in the C code :)
I am still figuring out how to selectively edit icon size, but the line and file you are looking for is #define ICON_DEFAULT_HEIGHT 16 and #define ICON_DEFAULT_WIDTH_16 in UI_interface_icons.h. For example, changing this height and width to 32 instead of 16 will double all of your icons; it would be ideal if you're scaling the rest of your interface (e.g. button padding) proportionately. This works for Blender source version 2.79. Hope this helps!