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(The original content is in Chinese and is converted through a translation program, which may differ from the original.)

Golden Source Engine is a 3D video game engine created by Valve in 1996. Many games have been created based on it.
I create maps in Counter-Strike for everyone to play with and to satisfy my creative desires. Sometimes, creators like me want to create transparency-related content in a map, but the existing rendering modes don't come close to what we want to express, so I thought about it, tested an idea and decided it would work relatively well. You might have a better idea. Welcome to brainstorm.

Creation method

• Create a gradient color and change it to "Index Color" in Image → Mode.

• Select "Local (Optional)", change the color number to "3", and select "Custom...", check "Transparency", and finally select "pattern" in the imitation color. (You can of course choose the color you like, and I chose red. Note that if there is a pattern in your texture, it is best to choose a color that has nothing to do with the color content of the pattern; You can also create this transparent effect first and then overlay the pattern on top.)