Some problems Using HE_Mesh library

Processing Libraries
1

Hi guys!
Just started working with Processing for my thesis project, a research on generative and procedural expressions used in graphic design.
I’m using the CANGenerativeTypography by Anon Owen folder to make some examples of this kind of generative typography to include in my research.
Only got one problem when I started to mess with the HEMesh library, as it was included in the folder.

I have this code:

import geomerative.; // geomerative library for text manipulation and point extraction
import wblut.hemesh.; // hemesh library section with main HE_Mesh class
import wblut.geom.*; // hemesh library section with geometry classes

RFont font; // geomerative font used for creating the 3D text
PShape shapeOriginal; // the PShape to store the original 3D mesh for fast display on the GPU
PShape shapeDeconstructed; // the PShape to store the deconstructed 3D mesh for fast display on the GPU
String input = “TYPE”; // the input string that is transformed into a 3D mesh

color[] colors = { #FAFAD2, #EEE8AA, #F0E68C, #DAA520, #FFD700, #FFA500, #FF8C00, #CD853F, #D2691E, #8B4513,#A0522D }; // gold

void setup() {
// Processing
size(1280, 720, P3D); // of course we need the 3D renderer
smooth(16); // nice and smooth! :wink:

// Geomerative
RG.init(this); // initialize the Geomerative library
RCommand.setSegmentator(RCommand.UNIFORMSTEP); // settings for the generated shape density
RCommand.setSegmentStep(3); // settings for the generated shape density
font = new RFont("…/…/Fonts/FreeSans.ttf", 350); // create the font used by Geomerative

// call the methods (see below) that do the actual work in this sketch
HE_Mesh mesh = createHemeshFromString(input); // create a 3D mesh from an input string (using Geomerative & Hemesh)
shapeOriginal = createPShapeFromHemesh(mesh, false); // store the original HE_Mesh in a PShape for fast display on the GPU
manipulateMesh(mesh); // apply modifiers to the HE_Mesh to subdivide and distort it
shapeDeconstructed = createPShapeFromHemesh(mesh, true); // store the deconstructed HE_Mesh in a PShape for fast display on the GPU
println(“Done.”);
}

void draw() {
background(0); // clear the background
perspective(PI/3.0, (float) width/height, 1, 1000000); // wide clipping planes
directionalLight(255, 255, 255, 1, 1, -1); // custom lights for more contrast
directionalLight(127, 127, 127, -1, -1, 1); // custom lights for more contrast
translate(width/2, height/2, map(mouseY, 0, height, 450, -100)); // center the shape on screen, zoom with mouseY
rotateY(map(mouseX, 0, width, -PI, PI)); // rotate around the Y axis with mouseX
shape(shapeOriginal); // display the original PShape
shape(shapeDeconstructed); // display the deconstucted PShape
}

// Turn a string into a 3D HE_Mesh
HE_Mesh createHemeshFromString(String s) {
println(“Creating mesh.”);

RMesh rmesh = font.toGroup(s).toMesh(); // create a 2D mesh from a text
rmesh.translate(-rmesh.getWidth()/2, rmesh.getHeight()/2); // center the mesh

ArrayList <WB_Triangle> triangles = new ArrayList <WB_Triangle> (); // holds the original 2D text mesh
ArrayList <WB_Triangle> trianglesFlipped = new ArrayList <WB_Triangle> (); // holds the flipped 2D text mesh
RPoint[] pnts;
WB_Triangle t, tFlipped;
WB_Point a, b, c;
// extract the triangles from geomerative’s 2D text mesh, then place them
// as hemesh’s 3D WB_Triangle’s in their respective lists (normal & flipped)
for (int i=0; i<rmesh.strips.length; i++) {
pnts = rmesh.strips[i].getPoints();
for (int j=2; j<pnts.length; j++) {
a = new WB_Point(pnts[j-2].x, pnts[j-2].y, 0);
b = new WB_Point(pnts[j-1].x, pnts[j-1].y, 0);
c = new WB_Point(pnts[j].x, pnts[j].y, 0);
if (j % 2 == 0) {
t = new WB_Triangle(a, b, c);
tFlipped = new WB_Triangle(c, b, a);
} else {
t = new WB_Triangle(c, b, a);
tFlipped = new WB_Triangle(a, b, c);
}
// add the original and the flipped triangle (to close the 3D shape later on) to their respective lists
triangles.add(t);
trianglesFlipped.add(tFlipped);
}
}

HE_Mesh tmesh = new HE_Mesh(new HEC_FromTriangles().setTriangles(triangles));
tmesh.modify(new HEM_Extrude().setDistance(100));
tmesh.add(new HE_Mesh(new HEC_FromTriangles().setTriangles(trianglesFlipped)));
tmesh.clean();
return tmesh;
}

// only the deconstructed mesh is manipulated
void manipulateMesh(HE_Mesh mesh) {
println(“Modifying mesh.”);

// modify all
mesh.modify(new HEM_VertexExpand().setDistance(-1)); // vertex expand all (to prevent z-fighting)
mesh.subdivide(new HES_CatmullClark()); // subdivide all

// modify selection
HE_Selection selection = getRandomSelection(mesh, 0.09); // get selection
mesh.modifySelected(new HEM_Extrude().setDistance(4).setRelative(true).setChamfer(0.2), selection); // extrude selection
mesh.subdivideSelected(new HES_CatmullClark(), selection); // subdivide selection
mesh.modifySelected(new HEM_VertexExpand().setDistance(6), selection); // vertex expand selection
mesh.subdivideSelected(new HES_CatmullClark(), selection); // subdivide selection

// modify random selection
mesh.modifySelected(new HEM_Extrude().setDistance(3).setRelative(true).setChamfer(0.35), getRandomSelection(mesh, 0.05)); // extrude random selection
mesh.modifySelected(new HEM_VertexExpand().setDistance(5), getRandomSelection(mesh, 0.075)); // vertex expand random selection
}

// get a random selection of faces from the mesh, given a certain threshold
HE_Selection getRandomSelection(HE_Mesh mesh, float threshold) {
HE_Selection selection = new HE_Selection(mesh);
for (HE_Face face : mesh.getFacesAsArray()) {
if (random(1) < threshold) selection.add(face);
}
return selection;
}

// store the geometry from a HE_Mesh in a PShape for quick display on the GPU
// in this sketch the per-vertex normals option is replaced with some convenience code
// to change the appearance of the two generated shapes from within this PShape creation method
PShape createPShapeFromHemesh(HE_Mesh mesh, boolean deconstructed) {
println(“Triangulating mesh.”);
mesh.triangulate(); // ensure it’s triangles only (CPU-intensive, but necessary)

// get all the shape data from the HE_Mesh
int[][] facesHemesh = mesh.getFacesAsInt();
float[][] verticesHemesh = mesh.getVerticesAsFloat();
HE_Face[] faceArray = mesh.getFacesAsArray();
WB_Coord normal = null;

println(“Storing mesh in PShape.”);
// create a PShape from the HE_Mesh shape data
PShape shape = createShape();
shape.beginShape(TRIANGLES);
if (deconstructed) {
shape.stroke(0, 125);
shape.strokeWeight(0.5);
} else {
shape.noStroke();
shape.fill(colors[4]);
}
for (int i=0; i<facesHemesh.length; i++) {
normal = faceArray[i].getFaceNormal();
if (deconstructed) { shape.fill(colors[int(random(colors.length))]); }
for (int j = 0; j < 3; j++) {
int index = facesHemesh[i][j];
float[] vertexHemesh = verticesHemesh[index];
shape.normal(normal.xf(), normal.yf(), normal.zf());
shape.vertex(vertexHemesh[0], vertexHemesh[1], vertexHemesh[2]);
}
}
shape.endShape();

// return the PShape
return shape;
}

When I try to run it I keep getting the same error message "the function modifySelected (HEM_Extrude , HE_Selection) does not exist.

I know it may seem as a noob question but I’m really trying to figure out what the problem is and I know I can find help on this forum so thanks a lot in advance!

2

Hi @jlnsrtr,

Hemesh library has recently been updated and rewritten for the occasion. Most of the past example sketches relying on it are now broken. I would suggest to:

  • look at the source code and example sketches here to see how these modifier functions have changed
  • ask @wblut for his help there if necessary

Here below a revised version of the problematic snippet

// modify selection
  HE_Selection selection = getRandomSelection(mesh, 0.09); // get selection
  mesh.getSelection("extruded").modify(new HEM_Extrude().setDistance(4).setRelative(true).setChamfer(0.2)); // extrude selection
  mesh.subdivideThreaded(new HES_CatmullClark()); // subdivide selection
  mesh.modify(new HEM_VertexExpand().setDistance(6)); // vertex expand selection
  mesh.subdivideThreaded(new HES_CatmullClark()); // subdivide selection

  // modify random selection
  mesh.getSelection("extruded").modify(new HEM_Extrude().setDistance(3).setRelative(true).setChamfer(0.35)); // extrude random selection
  mesh.modify(new HEM_VertexExpand().setDistance(5)); // vertex expand random selection
}

Unfortunately I don’t have the font file needed to run the code so I can’t test it for you. One thing is certain though, you need to figure out how to call the getRandomSelection() function from these modifiers.

2 Likes
3

Thanks a lot, will change that asap with the font loaded and see how it works, i thought that was a compatibility problem as this example is from 2015 or something like that and the library has been updated recently, also being new to processing didnt make things easier for me!
Thanks a lot!