1set_projection_viewport(3) Allegro manual set_projection_viewport(3)
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6 set_projection_viewport - Sets the viewport used to scale the output of
7 persp_project(). Allegro game programming library.
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10 #include <allegro.h>
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13 void set_projection_viewport(int x, int y, int w, int h);
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16 Sets the viewport used to scale the output of the persp_project() func‐
17 tion. Pass the dimensions of the screen area you want to draw onto,
18 which will typically be 0, 0, SCREEN_W, and SCREEN_H. Also don't forget
19 to pass an appropriate aspect ratio to get_camera_matrix later. The
20 width and height you specify here will determine how big your viewport
21 is in 3d space. So if an object in your 3D space is w units wide, it
22 will fill the complete screen when you run into it (i.e., if it has a
23 distance of 1.0 after the camera matrix was applied. The fov and
24 aspect-ratio parameters to get_camera_matrix also apply some scaling
25 though, so this isn't always completely true). If you pass -1/-1/2/2 as
26 parameters, no extra scaling will be performed by the projection.
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30 persp_project(3), get_camera_matrix(3), ex3d(3), excamera(3),
31 exquat(3), exscn3d(3), exstars(3), exzbuf(3)
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35Allegro version 4.4.3 set_projection_viewport(3)