Using mask & layers it is easy to map textures from one image onto another.This tutorial uses a sunburst gradient fill to create a grayscale mask then maps the color data from a different image onto it.

• For this tutorial we are going to create a shaded sphere.
•  Use the SELECTION tool to create a circular selection.

• Select white as the foreground color and black as the background color.
•  Select the FILL tool
   From the control palette select.
  (Fill Style sunburst gradient, Opacity 100, Tolerance 0)

• Fill the circular selection.

• Select MASKS > NEW > FROM IMAGE.
  (Source this window, Create mask from source opacity)

• Select FILE > OPEN and load your image.
• Select EDIT > COPY and copy the image to the clipboard.
  
  get fire.gif here if you want to use it.

• Make the mask active by clicking on its title bar.
• Select EDIT > PASTE AS NEW LAYER
•  Using the MOVEMENT tool left click and drag the new layer to position it.

• Select LAYERS > PROPERTIES
  (Blend Mode overlay, Opacity 100)

• Select LAYERS > MERGE > MERGE ALL(FLATTEN)
• Save your image in the desired format.
  
  * Images saved in .psp format retain all selections & layers