draw_vertex_texture(x, y, xtex, ytex)
| Argument | Description |
|---|---|
| x | The x coordinate of the vertex. |
| y | The y coordinate of the vertex. |
| xtex | The width of the texture sample to use. |
| ytex | The height of the texture sample to use. |
Returns: N/A
This function defines the position of a textured vertex for a primitive. The final look of the primitive will depend on the primitive type chosen to draw (See
draw_primitive_begin for more information), the order with which you add the vertexes to it and the position of the start point you set for the texture. To end and draw the primitive you
must call draw_primitive_end.
draw_set_colour(c_white);
The above code will draw a 4 vertex triangle strip (making a rectangle) textured with the texture held in the "tex" variable, and the whole texture will be used to cover the completed primitive.
You can also choose to draw only part of the texture over the surface of the primitive by setting the appropriate xtex/ytex position to sample to (these coordinates are also known as the UV
points). This point is defined by a value between 0 and 1 with the top left corner of the image to use being the (0,0) point and the bottom right corner being the (1,1) point. In this way you can texture a
primitive with only a part of the source image asset.
When drawing a textured primitive, the texture will be blended with the colour set by draw_set_colour. This means that to draw the texture
with no blending this should be set to c_white, as shown in the example below.
NOTE: For a texture to repeat it must be a power of two in size, ie: 32x32, 128x128, etc...
Example:
var tex = background_get_texture(background0);
draw_primitive_begin_texture(pr_trianglestrip, tex);
draw_vertex_texture(0, 480, 0, 1);
draw_vertex_texture(0, 0, 0, 0);
draw_vertex_texture(640, 480, 1, 1);
draw_vertex_texture(640, 0, 1, 0);
draw_primitive_end();