sdl_texture ->initialise: from=[image|size|graphical]Create with a copy of the pixels of an image or, given a size, with
transparent pixels. Given a graphical, the texture is as large as its
bounding box, including room for, e.g., a
glow, and holds the graphical drawn with Cairo. If the origin of the
graphical, the point (0,0) of its coordinates, is on the texture, it
becomes
sdl_texture<-hot_spot:
a figure drawn around its origin thus becomes a sprite that rotates
around that point. Without an argument the texture has no pixels until, e.g.,
a camera delivers a frame.
