Supplemental Patches

Specific Materials

3 min read

When writing your GLSL code for custom blocks, there are often situations where sections of code will need to be reused. Typically, this occurs when a specific material, say some metal, is part of a more complex block.

For example, consider the code for Galosphere’s combustion table,

if (color.b > 0.8) {  // Silver Part  
    #include "/lib/materials/specificMaterials/terrain/silverBlock.glsl"  
} else {  // Wood Part  
    #include "/lib/materials/specificMaterials/planks/darkOakPlanks.glsl"  
}

There is a silver part and a wood part. Their shaders are defined by GLSL files found under /lib/materials/specificMaterials.

In order to add the specific materials, you will need

  • a .glsl file to store shader code and
  • a .json file to denote which particles to apply the shader

These files should be placed under the specific_materials folder.

GLSL Format

The shader code will be injected into /shaders/programs/gbuffers_textured.glsl.

The shader code is evaluated at every vertex of the particle. In layman’s terms, the code is evaluated at every point on the particle.

Inputs

You have access to the following within the shader code. The data type is indicated in front. This is a non-exhaustive list and only touches on the most commonly used variables.

vec3 color.rgb - The color of the block within the block texture, for the currently evaluated part of the block. Each RGB value ranges between 0 and 1.
float color.a - The alpha value for translucent particles, ranging between 0 and 1.

vec2 lmCoordM - The lightmap at the currently evaluated part of the block . x is the blocklight, y is the skylight.

Outputs

The following can be modified within the code. The data type is indicated in front. This is a non-exhaustive list and only touches on the most commonly used variables.

float emission - Handles emissivity of the block.

vec2 lmCoordM - Used to modify the lightmap values.
vec3 color.rgb - Can be used to modify the color of the particle.
vec3 color.a - Can be used to modify the translucency of the particle.

float purkinjeOverwrite - Overwrites the darkness desaturation effect if set to 1.0 for that part of the particle.

discard - Used to decide not to render the particle.

JSON Format

The following are the parameters specified in the JSON. Bolded and italicized parameters are required.

name - The name of the type of particle handled by the shader.
glsl - The relative path to the .glsl file. Currently only searches for files within the same folder as the .json file. or within a sub-folder of that folder.

mat0 - The list of particle textures that the shader will be applied to. Note that you place particle textures in here, not the particles themselves.