5 - Editor Specific Shader Keywords
Q3Map2 Shader Manual
These instructions only affect the texture when it is seen in the Radiant editor. They should be grouped with the surface parameters but ahead of them in sequence.
This keyword creates a shader name in memory, but in the editor, it displays the TGA art image specified in qer_editorImage (in the example below this is textures/eerie/lavahell.tga).
The editor maps a texture using the size attributes of the TGA file used for the editor image. When that editor image represents a shader, any texture used in any of the shader stages will be scaled up or down to the dimensions of the editor image. If a 128x128 pixel image is used to represent the shader in the editor, then a 256x256 image used in a later stage will be shrunk to fit. A 64x64 image would be stretched to fit. Be sure to check this on bouncy, acceleration, and power-up pads placed on surfaces other than 256 x 256. Use tcMod scale to change the size of the stretched texture. Remember that tcMod scale 0.5 0.5 will double your image, while tcMod scale 2 2 will halve it.
The base_light and gothic_light shaders contain numerous uses of this. It can be very useful for making different light styles (mostly to change the light brightness) without having to create a new piece of TGA art for each new shader.
Script: Setting an editorImage
A brush marked with this instruction will not be affected by CSG subtract functions. It is especially useful for water and fog textures.
This keyword defines the percentage of transparency that a brush will have when seen in the editor (no effect on game rendering at all). It can have a positive value between 0 and 1. The higher the value, the less transparent the texture. Example: qer_trans 0.2 means the brush is 20% opaque and nearly invisible.
If you use qer_trans on a shader whose qer_editorImage has an alpha channel, the transparent areas of the editorImage will also be transparent in the editor. To keep the solid areas of the editorImage opaque, use a qer_trans value of "1.0". Useful for grates, windows, fences, etc.
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