1al_use_transform(3) al_use_transform(3)
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6 al_use_transform - Allegro 5 API
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9 #include <allegro5/allegro.h>
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11 void al_use_transform(const ALLEGRO_TRANSFORM *trans)
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14 Sets the transformation to be used for the the drawing operations on
15 the target bitmap (each bitmap maintains its own transformation). Ev‐
16 ery drawing operation after this call will be transformed using this
17 transformation. Call this function with an identity transformation to
18 return to the default behaviour.
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20 This function does nothing if there is no target bitmap.
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22 The parameter is passed by reference as an optimization to avoid the
23 overhead of stack copying. The reference will not be stored in the Al‐
24 legro library so it is safe to pass references to local variables.
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26 void setup_my_transformation(void)
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28 ALLEGRO_TRANSFORM transform;
29 al_translate_transform(&transform, 5, 10);
30 al_use_transform(&transform);
31 }
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33 Parameters:
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35 • trans - Transformation to use
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38 al_get_current_transform(3), al_transform_coordinates(3)
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42Allegro reference manual al_use_transform(3)