Constructor

CoglPrimitivenew_p2t2

Declaration [src]

CoglPrimitive*
cogl_primitive_new_p2t2 (
  CoglContext* context,
  CoglVerticesMode mode,
  int n_vertices,
  const CoglVertexP2T2* data
)

Description [src]

Provides a convenient way to describe a primitive, such as a single triangle strip or a triangle fan, that will internally allocate the necessary CoglAttributeBuffer storage, describe the position and texture coordinate attributes with CoglAttributes and upload your data.

For example to draw a convex polygon with texture mapping you can do:

CoglVertexP2T2 triangle[] =
{
  { 0,   300,  0.0, 1.0},
  { 150, 0,    0.5, 0.0},
  { 300, 300,  1.0, 1.0}
};
prim = cogl_primitive_new_p2t2 (COGL_VERTICES_MODE_TRIANGLE_FAN,
                                3, triangle);
cogl_primitive_draw (prim);

The value passed as n_vertices is initially used to determine how much can be read from data but it will also be used to update the CoglPrimitive n_vertices property as if cogl_primitive_set_n_vertices() were called. This property defines the number of vertices to read when drawing.

The primitive API doesn’t support drawing with sliced textures (since switching between slices implies changing state and so that implies multiple primitives need to be submitted). If your hardware doesn’t support non-power of two textures (For example you are using GLES 1.1) then you will need to make sure your assets are resized to a power-of-two size (though they don’t have to be square).