Overview
The Sobel Pack is shader which creates a blueprint/outline effect. It has two main modes: Geometric Outline and Texture Outline, as well as a mode which combines both. There is also options to texture the sky with a blueprint texture.
Geometric Outline
This mode is the default if no options are changed in the shader pack. It will put lines on any sudden changes in depth or facing direction. The threshold for when this happens can be modified with the "Depth Threshold" and "Normal Vector Threshold" options, but it is not recommended to modify these, as they are already tuned to practical values. It will not be able to capture any actual features of a texture, and only works with the geometry of the world.
Texture Outline
Warning: it is recommended to use a custom texture pack with this mode This mode puts lines on changes in colour over the screen. This mode is intended to be used with a custom texture pack, one which is mostly a solid colour, but has highlights for adding edges. You can modify the threshold at which a line is drawn with the "Color Threshold" option.
Blueprint Sky
The sky can be made to have a blueprint cube when the "Show Blueprint Sky" option is enabled. The blueprint sky can be made the texture of the world too, by using the "Use Sky As Background" option. To change the sky texture, unzip the shader pack, open the shaders folder, then the textures folder, and replace blueprint.png with your own blueprint texture.
NOTE: THIS SHADER PACK IS NOT AT ALL ENDORSED BY IRWIN SOBEL, I'M JUST A FAN
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