025-patterns

025-patterns

Using the IRMF editor, it can be difficult to see the details in the solid due to it not using surface normals.

Adding patterns to the model and displaying more than one color (by using more than one material) makes it much easier to visualize the solid.

Converting a single-material model to multiple materials involves:

• Adding the material names to the IRMF header
• Splitting the model's material value into multiple values using a pattern
• Assigning the resulting pattern to multiple material channels

Below are some simple examples.

cubed-1.irmf

Here is the IRMF logo with the cubed pattern applied:

/*{
  irmf: "1.0",
  materials: ["Red","Green"],
  max: [5,5,5],
  min: [-5,-5,-5],
  units: "mm",
}*/

float sphere(in float radius, in vec3 xyz) {
  float r = length(xyz);
  return r <= radius ? 1.0 : 0.0;
}

float cyl(in float radius, in vec2 uv) {
  float r = length(uv);
  return r <= radius ? 1.0 : 0.0;
}

vec2 cubed(in float value, in vec3 xyz) {
  vec3 v = step(0.5, mod(xyz, 1.0));
  int count = int(v.x + v.y + v.z);
  return count == 0 || count == 2 ? vec2(value, 0) : vec2(0, value);
}

void mainModel4(out vec4 materials, in vec3 xyz) {
  const float radius = 5.6;
  const float r2 = 3.3;
  float value = 1.0 - sphere(radius, xyz) - cyl(r2, xyz.yz) - cyl(r2, xyz.xz) - cyl(r2, xyz.xy);
  materials.xy = cubed(value, xyz - vec3(0.6));
}

• Try loading cubed-1.irmf now in the experimental IRMF editor!

• Use irmf-slicer to generate an STL or voxel approximation.

sphered-1.irmf

Here is the IRMF logo with the sphered pattern applied:

/*{
  irmf: "1.0",
  materials: ["Red","Green"],
  max: [5,5,5],
  min: [-5,-5,-5],
  units: "mm",
}*/

float sphere(in float radius, in vec3 xyz) {
  float r = length(xyz);
  return r <= radius ? 1.0 : 0.0;
}

float cyl(in float radius, in vec2 uv) {
  float r = length(uv);
  return r <= radius ? 1.0 : 0.0;
}

vec2 sphered(in float value, in vec3 xyz) {
  xyz = mod(xyz, 1.0) - vec3(0.5);
  return length(xyz) <= 0.5 ? vec2(value, 0) : vec2(0, value);
}

void mainModel4(out vec4 materials, in vec3 xyz) {
  const float radius = 5.6;
  const float r2 = 3.3;
  float value = 1.0 - sphere(radius, xyz) - cyl(r2, xyz.yz) - cyl(r2, xyz.xz) - cyl(r2, xyz.xy);
  materials.xy = sphered(value, xyz - vec3(0.6));
}

• Try loading sphered-1.irmf now in the experimental IRMF editor!

• Use irmf-slicer to generate an STL or voxel approximation.

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License

Copyright 2020 Glenn M. Lewis. All Rights Reserved.

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.