C-API I really don't understand how LCDSolidColor works with Fonts

SDK Development Discussion
1

When I draw text, I create a bitmap with a transparent background, and overlay that with some coloured text, black or white typically. Then this is just blitted wherever I need it.

But what I can't work out, is that if I paint kColorWhite text on a kColorBlack background it just doesn't show up. I have to use kColorXOR instead of the white, then it's fine.

/me shrugs

It would be great if someone could explain how this works to me... or indeed point me to some reference doco.

2

Looking at the code, it seems you’re passing the wrong type to setDrawMode which is producing the unexpected results you’re setting.

That API expects a LCDBitmapDrawMode rather than a LCDColor. From the docs:

void playdate->graphics->setDrawMode(LCDBitmapDrawMode mode);

typedef enum
{
	kDrawModeCopy,
	kDrawModeWhiteTransparent,
	kDrawModeBlackTransparent,
	kDrawModeFillWhite,
	kDrawModeFillBlack,
	kDrawModeXOR,
	kDrawModeNXOR,
	kDrawModeInverted
} LCDBitmapDrawMode;

You’ll either want to pass in the draw mode to your helper method, or do a conversion between LCDColor an LCDBitmapDrawMode (eg: kColorBlack should map to kDrawModeFillBlack).

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