1persp_project(3)                Allegro manual                persp_project(3)
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NAME

6       persp_project,  persp_project_f  -  Projects  a 3d point into 2d screen
7       space. Allegro game programming library.
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SYNOPSIS

10       #include <allegro.h>
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13       void persp_project(fixed x,  fixed  y,  fixed  z,  fixed  *xout,  fixed
14       *yout);
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16       void  persp_project_f(float  x,  float  y,  float z, float *xout, float
17       *yout);
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DESCRIPTION

20       Projects the 3d point (x, y, z)  into  2d  screen  space,  storing  the
21       result  in  (*xout,  *yout) and using the scaling parameters previously
22       set by calling set_projection_viewport(). This function  projects  from
23       the  normalized  viewing  pyramid, which has a camera at the origin and
24       facing along the positive z axis. The x axis runs  left/right,  y  runs
25       up/down,  and  z increases with depth into the screen. The camera has a
26       90 degree field of view, ie. points on the planes x=z and -x=z will map
27       onto  the  left  and  right edges of the screen, and the planes y=z and
28       -y=z map to the top and bottom of the screen. If you want  a  different
29       field of view or camera location, you should transform all your objects
30       with an appropriate viewing matrix, eg. to get the  effect  of  panning
31       the  camera  10 degrees to the left, rotate all your objects 10 degrees
32       to the right.
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SEE ALSO

38       set_projection_viewport(3), get_camera_matrix(3), ex3d(3), exstars(3)
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42Allegro                          version 4.2.2                persp_project(3)
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