Compose


Now the image is combined differently. Instead of just the black areas being transparent, the image is transparent in the dark places, opaque in the bright areas, and fades from transparent to opaque for all the shades in between. The result is that the white text is solid, the black background is transparent, but the grey edges fade out from solid at the edge of the white text to transparent where they are darker. This smooths the text into the background automatically. This will ONLY work on images where the area you wish to keep opaque is very bright (eg, white text), for normal images you will either have to use the Transparent Black option or create your own Alpha Channel.

Remember that you do not need to use two totally different images in Compose. Here we have cut out a brush (the mouth) and are using Compose to position it back onto the main image.

Now, this would be much nicer if we could 'cut away' the edges of the box we cut out and just leave the mouth. In Compose this is simple! Position the image where you want it to be (as we have done above) and click the 'Blend In/Out' option. Now, use the airbrush (or any of the other painting tools, except Smear - which works differently). Use the right mouse button to rub-thru to the background image, and the left mouse button to bring back the foreground image.

Now our 'second mouth' looks far more interesting! We can fix the image here, or we can go back to 'Edit Points' mode, move the rectangle around and reposition it somewhere else, although you have to spray around the mouth all again as it won't remember the changes you made when you were in Blend In/Out mode.

Well, actually, there is a way of doing that. It's a bit sneaky, but it's so useful that we'll have to share the secret. While in 'blend in/out' mode blend out the edges as before with the airbrush, and then from the main menu select Alpha/Paint Layer, Move Paint Layer to Alpha. This converts the area you have just painted into an Alpha Channel. Now, if you go back to 'Edit Points' mode you can move the mouth around with the new smooth edges and position it wherever you want, and it will always blend in smoothly with the background!

You must make sure the 'Compose Alpha' option is enabled for this to work. With it disabled the Alpha Channel works as normal, preventing compose affecting selected parts of the background.

Another way to move an irregular shaped object around the screen and reposition it with Compose is to use the freehand cut option from the brush cut-out. This will cut-out any shape area you draw around with the mouse and put it on a black background as a new buffer. If you now compose with the 'Transparent Black' option you can move the irregular shaped brush around the screen, scale it and position it wherever you like. If you wanted to 'stamp down' the brush many times and do not want to quit Compose, click on the FIX button in the toolbar instead of the OK button.

So far our use of Compose has been limited to the standard 'RubThru' mode, but Compose can use any of the paint modes to combine the two images together (although it is primarily of use with paint modes that work with secondary images, combining the 'Brightness Key' option with other paint modes, such as Brightness (set brightness to a negative value, use an anti-aliased text buffer, fix with the toolbar, move the image up and to the right by a few pixels, change paint mode back to RubThru and use OK to fix the image and quit Compose - you get your anti-aliased text plus a neat drop-shadow).

This is an example of Compose being used with the BrightMap paintmode, a face image is the primary image (Girl.JPG in Graphics/ExampleImages) and an image of Stonehenge (Scene3.JPG in Graphics/Scenes) in the secondary buffer (these images can be found in the example directory).

As with Photogenics in general, the key to using Compose is experimentation. Try out different combinations of effects and see what you get. Remember that you can change paint modes (RubMix, RubTint, RubTexture, BrightMap, DisplaceMap and RubEmboss all work very well with Compose) and that you can use the global transparency to alter the transparency of the composed image.

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