696 lines
23 KiB
JavaScript
696 lines
23 KiB
JavaScript
/** Copyright Stewart Allen <sa@grid.space> -- All Rights Reserved */
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import { util } from '../../geo/base.js';
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import { slicer } from '../../geo/slicer.js';
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import { newPolygon } from '../../geo/polygon.js';
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import { polygons as POLY } from '../../geo/polygons.js';
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import { newSlice, newTop } from '../../kiri/slice.js';
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import { doShells, doDiff, projectFlats, projectBridges } from '../fdm/slice.js';
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import { PNG } from '../../ext/pngjs.esm.js';
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import { SLA } from './driver.js';
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const tracker = util.pwait;
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let fill_cache;
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/**
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* DRIVER CONTRACT - runs in worker
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* @param {Object} settings
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* @param {Widget} Widget
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* @param {Function} onupdate (called with % complete and optional message)
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* @param {Function} ondone (called when complete with an array of Slice objects)
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*/
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export function sla_slice(settings, widget, onupdate, ondone) {
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let { minions } = self.kiri_worker,
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{ process, device, controller } = settings,
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isConcurrent = controller.threaded && minions.concurrent,
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work_total,
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work_remain;
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if (SLA.legacy && !self.OffscreenCanvas) {
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return ondone("browser lacks support for OffscreenCanvas",true);
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}
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// calculate % complete and call onupdate()
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function doupdate(work, msg) {
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onupdate(0.25 + ((work_total - work_remain) / work_total) * 0.75, msg);
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work_remain -= work;
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}
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// for each slice, perform a function and call doupdate()
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function forSlices(slices, work, fn, msg) {
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slices.forEach(function(slice,index) {
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fn(slice,index);
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doupdate(work / slices.length, msg)
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});
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}
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let smallDims = { x: 200, y: 125 };
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let largeDims = { x: 400, y: 300 };
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switch (device.deviceName) {
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case 'Anycubic.Photon':
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case 'Anycubic.Photon.S':
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// defaults above
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break;
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case 'Creality.Halot.One':
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case 'Creality.Halot.Max':
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case 'Creality.Halot.Sky':
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smallDims = { x: 116, y: 116 };
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largeDims = { x: 290, y: 290 };
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break;
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}
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let sws = self.kiri_worker.current.snap.url;
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let b64 = atob(sws.substring(sws.indexOf(',') + 1));
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let bin = Uint8Array.from(b64, c => c.charCodeAt(0));
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let img = new PNG();
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img.parse(bin, (err, data) => {
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SLA.preview = img;
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SLA.previewSmall = samplePNG(img, smallDims.x, smallDims.y);
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SLA.previewLarge = samplePNG(img, largeDims.x, largeDims.y);
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});
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let height = process.slaSlice || 0.05;
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async function onSliceDone(slices) {
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// remove empty slices
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slices = widget.slices = slices.filter(slice => slice.tops.length);
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if (!process.slaOpenTop && !process.xray) {
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// re-add last empty slice for closed top
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let cap = newSlice(bounds.max.z + height);
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cap.index = slices.last().index + 1;
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slices.push(cap);
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}
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// prepend raft layers to slices array
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if (process.slaSupportEnable && process.slaSupportLayers) {
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let layers = process.slaSupportLayers,
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zoff = height / 2,
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snew = [],
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polys = [],
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gap = process.slaSupportGap, // gap layers above raft
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grow = height, // union per layer expand
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off = 1 - (layers * grow); // starting union offset from part
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let outer = slices.forEach(slice => {
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// poly.clone prevents inner voids from forming
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polys.appendAll(slice.tops.map(t => t.poly.clone()));
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});
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// p.clone prevents inner voids from forming
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let union = POLY.union(polys, undefined, true).map(p => p.clone());
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let expand = POLY.expand(union, off, zoff, [], 1);
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let lastraft;
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for (let s=0; s<layers + gap; s++) {
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let slice = newSlice(zoff);
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slice.height = height;
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slice.index = snew.length;
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if (s < layers) {
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slice.synth = true;
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expand.forEach(u => {
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slice.tops.push(newTop(u.clone(true).setZ(zoff)));
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});
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expand = POLY.expand(expand, grow, zoff, [], 1);
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lastraft = slice;
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}
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snew.push(slice);
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zoff += height;
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}
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// compensate for midline start
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zoff -= height / 2;
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// replace slices with new appended array
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slices = widget.slices = snew.concat(slices.map(s => {
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s.tops.forEach(t => t.poly.setZ(s.z + zoff));
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s.index += snew.length;
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s.z += zoff;
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return s;
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}));
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// annotate widget for support generation
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widget.union = union;
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widget.lastraft = lastraft;
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}
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// re-connect slices into linked list for island/bridge projections
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for (let i=1; i<slices.length; i++) {
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slices[i-1].up = slices[i];
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slices[i].down = slices[i-1];
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}
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let solidLayers = Math.round(process.slaShell / process.slaSlice);
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// setup solid fill
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slices.forEach(function(slice) {
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slice.solids = [];
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});
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// compute total work for progress bar
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work_total = [
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5, // shell
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10, // diff
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solidLayers ? 10 : 0, // shell project
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solidLayers ? 10 : 0, // shell fill
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!solidLayers ? 10 : 0, // solid
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process.slaFillDensity && process.slaShell ? 60 : 0, // infill
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process.slaSupportEnable && process.slaSupportLayers && process.slaSupportDensity ? 100 : 0
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].reduce((t,v) => { return t+v });
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work_remain = work_total;
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forSlices(slices, 5, (slice,index) => {
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if (process.slaShell) {
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doShells(slice, 2, 0, process.slaShell);
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} else {
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doShells(slice, 1, 0);
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}
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}, "shells");
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forSlices(slices, 10, (slice) => {
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if (slice.synth) return;
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doDiff(slice, 0.000001, {
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sla: true,
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fakedown: !process.slaOpenBase
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});
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}, "delta");
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if (solidLayers) {
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forSlices(slices, 10, (slice) => {
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if (slice.synth) return;
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projectFlats(slice, solidLayers);
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projectBridges(slice, solidLayers);
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}, "project");
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async function doUnionSolid(slice) {
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if (slice.synth) return;
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let traces = POLY.nest(POLY.flatten(slice.topShells()));
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if (slice.solids) {
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let trims = slice.solids || [];
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traces.appendAll(trims);
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// slice.unioned = POLY.setZ(POLY.union(traces, undefined, true), slice.z);
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slice.unioned = POLY.setZ(await minions.union(traces), slice.z);
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} else {
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slice.unioned = traces;
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}
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}
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let promises = slices.map(slice => doUnionSolid(slice));
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await tracker(promises, (i, t) => {
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doupdate(10 / promises.length, "solid");
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});
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} else {
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forSlices(slices, 10, (slice) => {
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if (slice.synth) return;
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slice.unioned = slice.topPolys();
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}, "solid");
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}
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if (process.slaFillDensity && process.slaShell) {
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fill_cache = [];
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forSlices(slices, 60, (slice) => {
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if (slice.synth) return;
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fillPolys(slice, settings);
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}, "infill");
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}
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if (process.slaSupportEnable && process.slaSupportLayers && process.slaSupportDensity) {
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computeSupports(widget, process, progress => {
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doupdate(100 * progress, "support");
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});
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}
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doRender(widget);
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}
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let bounds = widget.getBoundingBox();
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let points = widget.getPoints();
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slicer.slice(points, {
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indices: process.indices || process.xray,
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union: controller.healMesh,
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debug: process.xray,
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xray: process.xray,
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zMin: bounds.min.z + height / 2,
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zMax: bounds.max.z,
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zInc: height,
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// slicer function (worker local or minion distributed)
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slicer(z, points, opts) {
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return (isConcurrent ? minions.sliceZ : slicer.sliceZ)(z, points, opts);
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},
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onupdate(v) {
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return onupdate(0.0 + v * 0.25);
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}
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}).then(output => {
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let slices = widget.slices = output.slices.map(data => {
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let { z, lines, groups } = data;
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let tops = POLY.nest(groups);
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return newSlice(z).addTops(tops);
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});
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onSliceDone(slices).then(ondone);
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});
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};
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function doRender(widget) {
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widget.slices.forEach(slice => {
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const render = slice.output(), lopacity = 0.6, line = 0x010101;
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if (slice.unioned) {
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slice.unioned.forEach(poly => {
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poly = poly.clone(true);//.move(widget.track.pos);
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render
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.setLayer("layers", { line, face: 0x0099cc, lopacity })
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.addAreas([poly], { outline: true });
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});
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} else if (slice.tops) {
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slice.tops.forEach(top => {
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let poly = top.poly;//.clone(true).move(widget.track.pos);
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render
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.setLayer("layers", { line, face: 0xfcba03, lopacity })
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.addAreas([poly], { outline: true });
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});
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}
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if (slice.supports) {
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slice.supports.forEach(poly => {
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render
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.setLayer("support", { line, face: 0xfcba03, lopacity })
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.addAreas([poly], { outline: true });
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});
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}
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});
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}
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function computeSupports(widget, process, progress) {
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let area = widget.union.reduce((t,p) => { return t + p.areaDeep() }, 0),
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perim = widget.union.reduce((t,p) => { return t + p.perimeter() }, 0),
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slices = widget.slices,
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length = slices.length,
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tot_mass = 0, // total widget "mass"
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tot_bear = 0; // total "mass-bearing" area
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let ops = slices.filter(slice => !slice.synth);
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// compute total "mass" by slice
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ops.forEach(slice => {
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slice.mass = slice.unioned.reduce((t,p) => { return t + p.areaDeep() }, 0);
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if (slice.up && slice.up.bridges) {
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slice.bear = slice.up.bridges.reduce((t,p) => { return t + p.areaDeep() }, 0);
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slice.bear_up = slice.up.bridges;
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tot_bear += slice.bear;
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} else {
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slice.bear = 0;
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}
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tot_mass += slice.mass;
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});
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let mass_per_bear = (tot_mass / tot_bear) * (1 / process.slaSupportDensity);
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// console.log({tot_mass, tot_bear, ratio: tot_mass / tot_bear, mass_per_bear});
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let first;
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ops.slice().map((s,i) => {
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if (!first && s.bear) {
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s.ord_first = first = true;
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}
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// 30x lowest to 1x highest
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s.ord_weight = Math.pow(30,((ops.length - i) / ops.length));
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return s;
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}).sort((a,b) => {
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if (a.ord_first) return -1;
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if (b.ord_first) return 1;
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return (b.bear * b.ord_weight) - (a.bear * a.ord_weight);
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}).forEach((slice, index) => {
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slice.ord_bear = index;
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})
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let rem_mass = tot_mass,
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rem_bear = tot_bear;
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// compute remaining mass, bearing surface, for each slice
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let run, runLast, runCount = 0, runList = [];
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ops.forEach(slice => {
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slice.rem_mass = rem_mass;
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slice.rem_bear = rem_bear;
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// slice.can_bear = slice.mass * mass_per_bear;
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slice.can_bear = slice.bear * mass_per_bear;
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rem_mass -= slice.mass;
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rem_bear -= slice.bear;
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});
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let ord = ops.sort((a,b) => {
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return a.ord_bear - b.ord_bear;
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});
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rem_mass = tot_mass;
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rem_bear = tot_bear;
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// in order of load bearing capability, select layer
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// and recompute the requirements on the slices below
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for (let i=0; i<ord.length; i++) {
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let slice = ord[i],
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bearing = Math.min(slice.can_bear, slice.rem_mass);
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// remove from slices below the amount of mass they have to bear
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for (let j=slice.index - 1; j>ops[0].index; j--) {
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slices[j].rem_mass -= bearing;
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}
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// remove total mass left to bear
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rem_mass -= bearing;
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slice.can_emit = true;
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if (rem_mass <= 0) {
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// console.log({break: i, of: ord.length});
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break;
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}
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}
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let seq = 0,
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seqLast = 0,
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spacing = (1 - process.slaSupportDensity) * 10,
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size = Math.bound(process.slaSupportSize / 2, 0.25, 1);
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// compute and project support pillars
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slices.forEach((slice,index) => {
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if (slice.can_emit) {
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if (seq === 0 || slice.index - seqLast > 5) {
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slice.bear_up.map(p => {
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return p.clone(true).setZ(slice.z);
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}).forEach(p => {
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projectSupport(process, slice, p, size, spacing);
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});
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seq++;
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} else if (seq > 5) {
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seq = 0;
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} else {
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seq++;
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}
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seqLast = slice.index;
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}
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progress(1 / slices.length);
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});
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// union support pillars
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slices.forEach(slice => {
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if (slice.supports) {
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slice.supports = POLY.union(slice.supports, 0, true);
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}
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});
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}
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function projectSupport(process, slice, poly, size, spacing) {
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let flat = poly.circularityDeep() > 0.1,
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arr = [ poly ];
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// insetting polys produces arrays. consume til gone
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while (arr.length) {
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poly = arr.shift();
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let out = [],
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seg = [],
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per = poly.perimeter(),
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crit = 0,
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polys = poly.clone(true).flattenTo([]);
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polys.forEach(p => p.forEachSegment((p1, p2) => {
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let rec = {dist: p1.distTo2D(p2), p1, p2};
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if (rec.dist >= spacing || slice.ord_first) crit++;
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seg.push(rec);
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}));
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seg.sort((a,b) => {
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return b.dist - a.dist;
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});
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// emit all critical (long) segments. min 3
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while (seg.length && (crit > 0 || out.length < 3)) {
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let {dist, p1, p2} = seg.shift();
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if (dist >= spacing) {
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// spaced along line
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let num = Math.ceil(dist / spacing) + 1,
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step = dist / num,
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pt = p1;
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while (num-- >= 0) {
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out.push(pt);
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pt = pt.offsetPointTo(p2, step);
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}
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crit--;
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} else {
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// line midpoint
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out.push(p1.offsetPointTo(p2, dist / 2));
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}
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}
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// drop points too close to other pillars
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if (!slice.ord_first)
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drop: for (let i=0; i<out.length; i++) {
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for (let j=i+1; j<out.length; j++) {
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if (out[i].distTo2D(out[j]) <= size) {
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out[i] = null;
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continue drop;
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}
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}
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if (slice.pillars) slice.pillars.forEach(rec => {
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if (out[i] && out[i].distTo2D(rec.point) <= size) {
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out[i] = null;
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}
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});
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}
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// mark support pillar for each point
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out.filter(p => p !== null)
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.forEach(p => {
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let track = projectPillar(process, slice, p, size, []);
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// find stunted pillars terminating on a face (not raft or merged)
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if (track.length && !(track.max || track.synth || track.merged)) {
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// remove stunted pillar
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track.forEach(rec => {
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let sp = rec.slice.supports;
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let rp = sp.indexOf(rec.pillar);
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if (rp >= 0) sp.splice(rp,1);
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});
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}
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});
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// inset polygon for flat area support
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if (flat) poly.offset(Math.max(0.2, 1 - process.slaSupportDensity), arr);
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}
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}
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function projectPillar(process, slice, point, size, track) {
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if (!slice.supports) slice.supports = [];
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if (!slice.pillars) slice.pillars = [];
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let points = process.slaSupportPoints,
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pillar = newPolygon()
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.centerCircle(point, size/2, points, true)
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.setZ(slice.z),
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max = process.slaSupportSize,
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inc = process.slaSlice/2,
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end = false, // center intersects
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over = [], // overlapping points
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safe = [], // non-overlapping points
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low = slice.index < process.slaSupportGap + process.slaSupportLayers;
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track.min = track.min ? Math.min(track.min, size) : size;
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track.max = (track.max ? true : false) || size >= max;
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track.synth = track.synth || slice.synth;
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slice.tops.forEach(t => {
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if (track.length > 3 && point.isInPolygon(t.poly)) {
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end = true;
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}
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pillar.points.forEach(p => {
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let isin = p.isInPolygon(t.poly);// || p.nearPolygon(t.poly, 0.001);
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if (isin) {
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over.push(p);
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} else {
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safe.push(p);
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}
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});
|
|
});
|
|
|
|
if (end) {
|
|
// backtrack shrinking pillars to point if
|
|
// not landing on the base and size is max'd
|
|
if (!slice.synth && track.max) {
|
|
let nusize = track.min;
|
|
while (track.length) {
|
|
let prec = track.pop(),
|
|
npil = newPolygon()
|
|
.centerCircle(prec.point, nusize/2, points, true)
|
|
.setZ(prec.slice.z),
|
|
spos = prec.slice.supports.indexOf(prec.pillar);
|
|
// if we find our old pillar, replace
|
|
if (spos >= 0) {
|
|
prec.slice.supports[spos] = npil;
|
|
nusize += inc;
|
|
}
|
|
if (nusize > prec.size) {
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
return track;
|
|
}
|
|
|
|
let nextpoint = point;
|
|
|
|
if (over.length) {
|
|
// move toward average of safe (non-overlapping) points
|
|
if (safe.length) {
|
|
let x = 0, y = 0;
|
|
safe.forEach(p => { x += p.x; y += p.y });
|
|
x /= safe.length;
|
|
y /= safe.length;
|
|
nextpoint = point.offsetPointTo({x, y, z:slice.z}, inc);
|
|
}
|
|
// once max'ed out, can only shrink in size
|
|
if (track.max) {
|
|
size -= inc;
|
|
}
|
|
} else if (!track.max || low) {
|
|
size += inc;
|
|
if (low) max += (process.slaSupportGap * process.slaSlice * 2);
|
|
}
|
|
|
|
if (size < track.min) {
|
|
return track;
|
|
}
|
|
|
|
// let close = [];
|
|
// for (let i=0; i<slice.pillars.length; i++) {
|
|
// let p = slice.pillars[i].point;
|
|
// let d = point.distTo2D(p);
|
|
// // terminate if we're inside another pillar
|
|
// if (d < inc) {
|
|
// track.merged = true;
|
|
// return track;
|
|
// }
|
|
// if (d <= process.slaSupportSize * 1.5) {
|
|
// close.push(p);
|
|
// }
|
|
// }
|
|
// if (close.length) {
|
|
// let newp = point.clone();
|
|
// close.forEach(p => {
|
|
// newp.x += p.x;
|
|
// newp.y += p.y;
|
|
// });
|
|
// newp.x /= (close.length + 1);
|
|
// newp.y /= (close.length + 1);
|
|
// nextpoint = point.offsetPointTo(newp, inc);
|
|
// }
|
|
|
|
slice.supports.push(pillar);
|
|
slice.pillars.push({point, pillar, size});
|
|
track.push({slice, point, pillar, size});
|
|
if (slice.down) {
|
|
projectPillar(process, slice.down, nextpoint, Math.min(size, max), track);
|
|
}
|
|
return track;
|
|
}
|
|
|
|
function fillPolys(slice, settings) {
|
|
let process = settings.process,
|
|
device = settings.device,
|
|
polys = slice.unioned,
|
|
bounds = settings.bounds,
|
|
width = bounds.max.x - bounds.min.x,
|
|
depth = bounds.max.y - bounds.min.y,
|
|
max = Math.max(width,depth),
|
|
seq = Math.round(process.slaFillLine / process.slaSlice),
|
|
linew = process.slaFillLine,
|
|
units_w = (width / linew) * process.slaFillDensity,
|
|
units_d = (depth / linew) * process.slaFillDensity,
|
|
step_x = width / units_w,
|
|
step_y = depth / units_d,
|
|
start_x = -(width / 2),
|
|
start_y = -(depth / 2),
|
|
end_x = width / 2,
|
|
end_y = depth / 2,
|
|
fill = [];
|
|
|
|
let seq_i = Math.floor(slice.index / seq),
|
|
seq_c = seq_i % 4,
|
|
cached = fill_cache[seq_c];
|
|
|
|
if (!cached && seq_c !== 1)
|
|
for (let x=start_x; x<end_x; x += step_x) {
|
|
fill.push(
|
|
newPolygon().centerRectangle({
|
|
x: x + step_x/2,
|
|
y: 0,
|
|
z: slice.z
|
|
}, linew, depth)
|
|
);
|
|
}
|
|
|
|
if (!cached && seq_c !== 3)
|
|
for (let y=start_y; y<end_y; y += step_y) {
|
|
fill.push(
|
|
newPolygon().centerRectangle({
|
|
x: 0,
|
|
y: y + step_y/2,
|
|
z: slice.z
|
|
}, width, linew)
|
|
);
|
|
}
|
|
|
|
if (!cached) {
|
|
fill = POLY.union(fill, 0, true);
|
|
fill_cache[seq_c] = fill;
|
|
} else {
|
|
fill = cached.slice().map(p => p.clone(true).setZ(slice.z));
|
|
}
|
|
|
|
fill = POLY.trimTo(fill, slice.tops.map(t => t.poly));
|
|
fill = POLY.union(slice.unioned.appendAll(fill), 0, true);
|
|
|
|
slice.unioned = fill;
|
|
}
|
|
|
|
function pixAt(png,x,y) {
|
|
let idx = (x + png.width * y) * 4;
|
|
let dat = png.data;
|
|
return [
|
|
dat[idx++],
|
|
dat[idx++],
|
|
dat[idx++],
|
|
dat[idx++]
|
|
];
|
|
}
|
|
|
|
function averageBlock(png,x1,y1,x2,y2) {
|
|
let val = [0, 0, 0, 0], count = 0, x, y, z, v2;
|
|
for (x=x1; x<x2; x++) {
|
|
for (y=y1; y<y2; y++) {
|
|
v2 = pixAt(png,x,y);
|
|
for (z=0; z<4; z++) {
|
|
val[z] += v2[z];
|
|
}
|
|
count++;
|
|
}
|
|
}
|
|
for (z=0; z<4; z++) {
|
|
val[z] = Math.abs(val[z] / count);
|
|
}
|
|
return val;
|
|
};
|
|
|
|
function samplePNG(png, width, height) {
|
|
let th = width, tw = height,
|
|
aspect = width / height, // was fixed at 4/3 for photon
|
|
ratio = png.width / png.height,
|
|
buf = new Uint8Array(th * tw * 4),
|
|
div, xoff, yoff, dx, ex, dy, ey, bidx, pixval;
|
|
|
|
if (ratio >= aspect) {
|
|
div = png.height / tw;
|
|
xoff = Math.round((png.width - (th * div)) / 2);
|
|
yoff = 0;
|
|
} else {
|
|
div = png.width / th;
|
|
xoff = 0;
|
|
yoff = Math.round((png.height - (tw * div)) / 2);
|
|
}
|
|
|
|
for (let y=0; y<tw; y++) {
|
|
dy = Math.round(y * div + yoff);
|
|
if (dy < 0 || dy > png.height) continue;
|
|
ey = Math.round((y+1) * div + yoff);
|
|
for (let x=0; x<th; x++) {
|
|
dx = Math.round(x * div + xoff);
|
|
if (dx < 0 || dx > png.width) continue;
|
|
ex = Math.round((x+1) * div + xoff);
|
|
bidx = (y * th + x) * 4;
|
|
pixval = averageBlock(png,dx,dy,ex,ey);
|
|
buf[bidx+0] = pixval[0];
|
|
buf[bidx+1] = pixval[1];
|
|
buf[bidx+2] = pixval[2];
|
|
buf[bidx+3] = pixval[3];
|
|
}
|
|
}
|
|
|
|
return {width, height, data:buf, png};
|
|
}
|