1ALLEGRO_SHADER_TYPE(3) ALLEGRO_SHADER_TYPE(3)
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6 ALLEGRO_SHADER_TYPE - Allegro 5 API
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9 #include <allegro5/allegro.h>
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11 typedef enum ALLEGRO_SHADER_TYPE ALLEGRO_SHADER_TYPE;
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14 Used with al_attach_shader_source(3) and al_attach_shad‐
15 er_source_file(3) to specify how to interpret the attached source.
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17 ALLEGRO_VERTEX_SHADER
18 A vertex shader is executed for each vertex it is used with.
19 The program will output exactly one vertex at a time.
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21 When Allegro’s graphics are being used then in addition to all
22 vertices of primitives from the primitives addon, each drawn
23 bitmap also consists of four vertices.
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25 ALLEGRO_PIXEL_SHADER
26 A pixel shader is executed for each pixel it is used with. The
27 program will output exactly one pixel at a time - either in the
28 backbuffer or in the current target bitmap.
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30 With Allegro’s builtin graphics this means the shader is for ex‐
31 ample called for each destination pixel of the output of an
32 al_draw_bitmap(3) call.
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34 A more accurate term for pixel shader would be fragment shader
35 since one final pixel in the target bitmap is not necessarily
36 composed of only a single output but of multiple fragments (for
37 example when multi-sampling is being used).
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40 5.1.0
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44Allegro reference manual ALLEGRO_SHADER_TYPE(3)