I created a gif using a 3D file loader addon in openFrameworks. I uploaded a skull .stl file that rotates back and forth about 26 degrees in a non-linear motion. In the background I drew a bunch of diagonal lines that scroll across the screen. I didn’t realize how visually overwhelming this effect would be, but I kind of like it. It was pretty difficult getting a handle of the 3d addon at first, but I was eventually able to work it out. Unfortunately the GIF does not loop; this was an exporting error. Reload this page to see the skull shake its head.

A bit of code:

#include "ofApp.h"

//--------------------------------------------------------------
void testApp::setup(){
   
    ofBackgroundHex(0x222222);
    ofSetVerticalSync(true);
    glEnable(GL_DEPTH_TEST);   
    light.enable();

    // Move off default colors
    light.setDiffuseColor(ofColor::fromHsb(180, 70, 75));
    light.setAmbientColor(ofColor::fromHsb(180, 150, 200));

    ofSetLogLevel(OF_LOG_VERBOSE);
    bSaveModel = false;
    stlImporter.loadSTL(ofToDataPath("skull.stl"));

    drawMode = facets;
}

//--------------------------------------------------------------

void testApp::update(){
    if(bSaveModel){
        bSaveModel = false;
        vector& facets = stlImporter.getFacets();
        int numFacets = facets.size();
        stlExporter.beginModel("some model");
        for(int i=0; i<numFacets; i++){
            stlExporter.addTriangle(facets[i].vert1, facets[i].vert2, facets[i].vert3, facets[i].normal);
        }

        stlExporter.useASCIIFormat(true); //export as ASCII (default is binary)
        stlExporter.saveModel(ofToDataPath("testASCII.stl"));
        stlExporter.useASCIIFormat(false); //export as binary
        stlExporter.saveModel(ofToDataPath("testBin.stl"));
    }
}

//--------------------------------------------------------------
void testApp::draw(){
    // Enlarge our model
    float rachelScale = ofGetWidth()/720.0;
    stlImporter.rescaleModel(350 * rachelScale);

    //ofLog() << "hi there" << 1;
    int nFramesIWant = 10;
    float rotationRange = 30;
    int whichFrame = ofGetFrameNum() % nFramesIWant;
    printf ("Which frame I'm on = %d\n", whichFrame);
    float t = ofMap (whichFrame, 0,9, 0,TWO_PI);
    float cost = cos(t); // 0...1
    float amountToRotateSomething = rotationRange/2.0 * cost;
    //float amountToRotateSomething = ofMap (whichFrame, 0,9, 0-rotationRange/2, rotationRange/2);

    ofPushMatrix();
    ofTranslate (ofGetWidth()/2, ofGetHeight()/2,0);

    //red X axis
    // ofSetColor (255,0,0);
    // ofLine(0,0,0, 1000,0,0);

    //green Y axis
    // ofSetColor (0,255,0);
    // ofLine(0,0,0, 0,1000,0);

    ofRotateY ( amountToRotateSomething );
    ofRotateX ( 70);
    ofRotateZ (-90);
    ofTranslate (0,0, 0-100*rachelScale); 

    ofSetColor (200,200,200);
    if(drawMode == normals) {
        stlImporter.drawNormals();
    }
    else if(drawMode == wire) {
         stlImporter.drawWireFrame();
    }
    else if(drawMode == facets) {
         stlImporter.drawFacets();
    }

    ofPopMatrix();
    // ofSetHexColor(0xe0d6ff);

    //diagonal stripes
    ofPushMatrix();
    ofScale(1.8*rachelScale,1.8*rachelScale);
    ofTranslate (-29*rachelScale,-29*rachelScale,-80*rachelScale);

    //finding the edge of the screen
    //red X axis for diagonal lines

    ofSetColor (255,0,0);
    ofLine(0,1,0, 1000,0,0);
    //green Y axis for diagonal lines
    ofSetColor (0,255,0);
    ofLine(1,0,0, 0,1000,0);

    //initializing x,y arrays for diagonal lines
    const int length = (720+50);
    float xPos [length] = {};
    float yPos [length] = {};

    //populating arrays
    for ( int i = 0; i < length; i++) {
        xPos[i] += 10*i-50;
    }

    for (int j = 0; j < length; j++) {
        yPos[j] += 10*j-50;
    }

    ofDisableLighting();
    //drawing diagonal lines
    ofSetColor(255);
    glLineWidth(3);

    int moveAmount = 0;
    moveAmount = ofGetFrameNum() % nFramesIWant;
    for(int i=0; i<720; i++){
        ofLine(xPos[i]+moveAmount*2,0,0, 0,yPos[i]+moveAmount*2,0);
    }

    ofEnableLighting();
    ofPopMatrix();
    //ofSaveFrame();
}