
Custom Outline lets you change the colour, opacity and thickness of Minecraft's block selection outline.
By default, it comes with the colour #ffcc00 
The easiest way to create a custom pack is to use the Custom Outline Generator.
Select your settings, choose your Minecraft version, and download the generated pack.
Custom Outline v1.1.0 supports Respackopts.
Install Respackopts and LibJF, then open the Custom Outline settings through Respackopts or Mod Menu. You can change the outline colour, opacity, thickness, and animation.
The newest packs use Respackopts format v13 and support the newer preset system. Older packs use format v12, which supports the main settings but not the newer preset-file system.

You can manually edit the shader if you prefer.
Open:
assets/minecraft/shaders/core/rendertype_lines.vsh
Find the #ifndef respackopts_loaded section and change the colour values:
#define customOutline_outline_red 255
#define customOutline_outline_green 204
#define customOutline_outline_blue 0
#define customOutline_outline_opacity 100
#define customOutline_outline_thickness 1.0
Save the file and press F3 + T in Minecraft to reload the pack.
To use the rainbow animation, replace:
#define customOutline_outline_mode_static
with:
#define customOutline_outline_mode_rainbow
Custom Outline is not compatible with shaderpacks that replace Minecraft's core shaders, such as Iris or OptiFine shaderpacks.
If you want to use shaders with a custom outline, use a shaderpack with its own outline settings, such as:
Make sure you are using the version selected for your Minecraft installation.
Install Respackopts and LibJF for your Minecraft version, then restart the game.
Make sure Custom Outline is enabled and press F3 + T to reload the resource pack.
Also check that another resource pack is not overriding the same shader.
Shaderpacks may replace the shader used by Custom Outline. Disable the shaderpack or use its built-in outline settings instead.
Need help or have a suggestion?
Reach out on GitHub or join the Support Discord.
Custom Outline is Β© NotToBlame.
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