Attributes such as bump, transparency, and incandescence paint as grayscale values—you must do a software render to see their effect. While this is to be expected, there may be times when you want to see the effects of your brush strokes as you paint them. You can do this using IPR.

To preview painting in IPR

1. Turn on Update on Stroke in the File Textures section of the 3D Paint Tool Settings editor.
2. Start an IPR render of the model. For details, see the Rendering guide.
3. Start painting. As you paint, the image will refresh to show the rendered effect of your last painted stroke.
   NoteYou cannot erase with Update on Stroke turned on. If you need to erase, simply click Save Textures whenever you want to update the IPR image.

   You can use the 3D Paint Tool while High Quality Rendering is turned on; this enables you to preview attributes such as bump and transparency while painting them, however you cannot see the stroke itself while it is being painted, since the texture is updated only at the end of each stroke.