SYNOPSIS
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#include <allegro5/allegro_primitives.h>
int al_draw_prim(const void* vtxs, const ALLEGRO_VERTEX_DECL* decl,
ALLEGRO_BITMAP* texture, int start, int end, int type)
DESCRIPTION
Draws a subset of the passed vertex array.
Parameters:
- texture - Texture to use, pass NULL to use only color shaded primitves
- vtxs - Pointer to an array of vertices
- decl - Pointer to a [vertex declaration]al_create_vertex_decl(3alleg5). If set to NULL, the vertices are assumed to be of the ALLEGRO_VERTEX(3alleg5) type
- start - Start index of the subset of the vertex array to draw
- end - One past the last index of the subset of the vertex array to draw
- type - A member of the ALLEGRO_PRIM_TYPE(3alleg5) enumeration, specifying what kind of primitive to draw
Returns: Number of primitives drawn
For example to draw a textured triangle you could use:
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ALLEGRO_COLOR white = al_map_rgb_f(1, 1, 1); ALLEGRO_VERTEX v[] = { {.x = 128, .y = 0, .z = 0, .color = white, .u = 128, .v = 0}, {.x = 0, .y = 256, .z = 0, .color = white, .u = 0, .v = 256}, {.x = 256, .y = 256, .z = 0, .color = white, .u = 256, .v = 256}}; al_draw_prim(v, NULL, texture, 0, 3, ALLEGRO_PRIM_TRIANGLE_LIST);