allegro.cc

Manual

Transformations

• ALLEGRO_TRANSFORM
• al_copy_transform
• al_use_transform
• al_get_current_transform
• al_invert_transform
• al_check_inverse
• al_identity_transform
• al_build_transform
• al_translate_transform
• al_rotate_transform
• al_scale_transform
• al_transform_coordinates
• al_compose_transform

al_compose_transform

void al_compose_transform(ALLEGRO_TRANSFORM *trans, const ALLEGRO_TRANSFORM *other)

Compose (combine) two transformations by a matrix multiplication.

trans := trans other

Note that the order of matrix multiplications is important. The effect of applying the combined transform will be as if first applying trans and then applying other and not the other way around.

Parameters:

• trans - Transformation to alter
• other - Transformation used to transform trans

Most helpful discussions:

• Transform / Translate
• Using Sine And Cosine For Rotation
• First person camera using transformations
• [A5] Trying to understand projection transformations
• [A5] Trying to understand transformations
• Transformations in allegro
• Is composing horz + vert shear the same thing as shearing both?
• Pushing allegro performance (sprites per second) to its limits
• [A5] al_draw_bitmap() vs al_draw_rotated_bitmap()
• Allegro Fonts in 3D space and with a custom frustum

Other recent discussions:

• fastest way to plot pixels A5
• [5.0rc2] OpenGL/Deferred drawing CPU use