al_draw_prim (3alleg5)

• #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)
  
  

Draws a subset of the passed vertex buffer.

Parameters:

\[bu]

texture - Texture to use, pass 0 to use only color shaded primitves

\[bu]

vtxs - Pointer to an array of vertices

\[bu]

decl - Pointer to a vertex declaration. If set to NULL, the vertices are assumed to be of the ALLEGRO_VERTEX type

\[bu]

start - Start index of the subset of the vertex buffer to draw

\[bu]

end - One past the last index of subset of the vertex buffer to draw

\[bu]

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:

• 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);
  
  

ALLEGRO_VERTEX(3alleg5), ALLEGRO_PRIM_TYPE(3alleg5), ALLEGRO_VERTEX_DECL(3alleg5), al_draw_indexed_prim(3alleg5)