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cross_product(3alleg4) Allegro manual cross_product(3alleg4)

cross_product, cross_product_f - Calculates the cross product. Allegro game programming library.

#include <allegro.h>

void cross_product(fixed x1, y1, z1, x2, y2, z2, *xout, *yout, *zout);

void cross_product_f(float x1, y1, z1, x2, y2, z2, *xout, *yout, *zout);

Calculates the cross product (x1, y1, z1) x (x2, y2, z2), storing the result in (*xout, *yout, *zout). The cross product is perpendicular to both of the input vectors, so it can be used to generate polygon normals.

dot_product(3alleg4), polygon_z_normal(3alleg4), normalize_vector(3alleg4), exstars(3alleg4)

version 4.4.3 Allegro