Man page - ttf_setfontsize(3)

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Package: libsdl3-ttf-doc
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TTF_SetFontSize - Set a font’s size dynamically.

Defined in SDL3_ttf/SDL_ttf.h

#include "SDL3_ttf/SDL_ttf.h"

bool TTF_SetFontSize(TTF_Font *font, float ptsize);

This updates any TTF_Text
objects using this font, and clears already-generated glyphs, if any, from the cache.

	font		the font to resize.
	ptsize		the new point size.

Returns true on success or false on failure; call SDL_GetError() for more information.

This function should be called on the thread that created the font.

This function is available since SDL_ttf 3.0.0.