Normal are created using an RGB (red, green, and blue) image, where each color channel in the image represents the X, Y, and Z component of the surface normal at each texel of the map. This means a normal map has three channels, with each containing positive or negative values.
• The red channel (R) corresponds to the X component of the surface normal vector.
• The green channel (G) represents the Y component of the surface normal vector.
• The blue channel (B) represents the Z component of the surface normal vector.
All three channels are used together to provide explicit orientation data for each texel, which is used during rendering to enhance the lighting and shading effects on the 3D model.