Step 1: Defining a Custom Vertex Format

Before using textures, a custom vertex format that includes texture coordinates must be used. Texture coordinates tell Microsoft?Direct3D?where to place a texture for each vector in a primitive. Texture coordinates range from 0.0 to 1.0, where (0.0, 0.0) represents the top-left side of the texture and (1.0, 1.0) represents the lower-right side of the texture.

The following sample code shows how the Texture sample project sets up its custom vertex format to include texture coordinates.

// A structure for our custom vertex type. Texture coordinates were added.
struct CUSTOMVERTEX
{
    D3DXVECTOR3 position; // The position
    D3DCOLOR    color;    // The color
#ifndef SHOW_HOW_TO_USE_TCI
    FLOAT       tu, tv;   // The texture coordinates
#endif
};

// Our custom FVF, which describes our custom vertex structure
#ifdef SHOW_HOW_TO_USE_TCI
#define D3DFVF_CUSTOMVERTEX (D3DFVF_XYZ|D3DFVF_DIFFUSE)
#else
#define D3DFVF_CUSTOMVERTEX (D3DFVF_XYZ|D3DFVF_DIFFUSE|D3DFVF_TEX1)
#endif

For more information about texture coordinates, see Texture Coordinates.

Now that a custom vertex type has been defined, the next step is to load a texture and create a cylinder, as described in Step 2: Initializing Screen Geometry.