AmmoDebugDrawer.js

/* global Ammo */

export const DefaultBufferSize = 3 * 1000000;

export const AmmoDebugConstants = {
  NoDebug: 0,
  DrawWireframe: 1,
  DrawAabb: 2,
  DrawFeaturesText: 4,
  DrawContactPoints: 8,
  NoDeactivation: 16,
  NoHelpText: 32,
  DrawText: 64,
  ProfileTimings: 128,
  EnableSatComparison: 256,
  DisableBulletLCP: 512,
  EnableCCD: 1024,
  DrawConstraints: 1 << 11, //2048
  DrawConstraintLimits: 1 << 12, //4096
  FastWireframe: 1 << 13, //8192
  DrawNormals: 1 << 14, //16384
  MAX_DEBUG_DRAW_MODE: 0xffffffff
};

const setXYZ = function(array, index, x, y, z) {
  index *= 3;
  array[index + 0] = x;
  array[index + 1] = y;
  array[index + 2] = z;
};

/**
 * An implementation of the btIDebugDraw interface in Ammo.js, for debug rendering of Ammo shapes
 * @class AmmoDebugDrawer
 * @param {Uint32Array} indexArray
 * @param {Float32Array} verticessArray
 * @param {Float32Array} colorsArray
 * @param {Ammo.btCollisionWorld} world
 * @param {object} [options]
 */
export const AmmoDebugDrawer = function(indexArray, verticesArray, colorsArray, world, options) {
  this.world = world;
  options = options || {};

  this.verticesArray = verticesArray;
  this.colorsArray = colorsArray;
  this.indexArray = indexArray;

  this.debugDrawMode = options.debugDrawMode || AmmoDebugConstants.DrawWireframe;

  this.index = 0;
  if (this.indexArray) {
    Atomics.store(this.indexArray, 0, this.index);
  }

  this.enabled = false;

  this.debugDrawer = new Ammo.DebugDrawer();
  this.debugDrawer.drawLine = this.drawLine.bind(this);
  this.debugDrawer.drawContactPoint = this.drawContactPoint.bind(this);
  this.debugDrawer.reportErrorWarning = this.reportErrorWarning.bind(this);
  this.debugDrawer.draw3dText = this.draw3dText.bind(this);
  this.debugDrawer.setDebugMode = this.setDebugMode.bind(this);
  this.debugDrawer.getDebugMode = this.getDebugMode.bind(this);
  this.debugDrawer.enable = this.enable.bind(this);
  this.debugDrawer.disable = this.disable.bind(this);
  this.debugDrawer.update = this.update.bind(this);

  this.world.setDebugDrawer(this.debugDrawer);
};

AmmoDebugDrawer.prototype = function() {
  return this.debugDrawer;
};

AmmoDebugDrawer.prototype.enable = function() {
  this.enabled = true;
};

AmmoDebugDrawer.prototype.disable = function() {
  this.enabled = false;
};

AmmoDebugDrawer.prototype.update = function() {
  if (!this.enabled) {
    return;
  }

  if (this.indexArray) {
    if (Atomics.load(this.indexArray, 0) === 0) {
      this.index = 0;
      this.world.debugDrawWorld();
      Atomics.store(this.indexArray, 0, this.index);
    }
  } else {
    this.index = 0;
    this.world.debugDrawWorld();
  }
};

AmmoDebugDrawer.prototype.drawLine = function(from, to, color) {
  const heap = Ammo.HEAPF32;
  const r = heap[(color + 0) / 4];
  const g = heap[(color + 4) / 4];
  const b = heap[(color + 8) / 4];

  const fromX = heap[(from + 0) / 4];
  const fromY = heap[(from + 4) / 4];
  const fromZ = heap[(from + 8) / 4];
  setXYZ(this.verticesArray, this.index, fromX, fromY, fromZ);
  setXYZ(this.colorsArray, this.index++, r, g, b);

  const toX = heap[(to + 0) / 4];
  const toY = heap[(to + 4) / 4];
  const toZ = heap[(to + 8) / 4];
  setXYZ(this.verticesArray, this.index, toX, toY, toZ);
  setXYZ(this.colorsArray, this.index++, r, g, b);
};

//TODO: figure out how to make lifeTime work
AmmoDebugDrawer.prototype.drawContactPoint = function(pointOnB, normalOnB, distance, lifeTime, color) {
  const heap = Ammo.HEAPF32;
  const r = heap[(color + 0) / 4];
  const g = heap[(color + 4) / 4];
  const b = heap[(color + 8) / 4];

  const x = heap[(pointOnB + 0) / 4];
  const y = heap[(pointOnB + 4) / 4];
  const z = heap[(pointOnB + 8) / 4];
  setXYZ(this.verticesArray, this.index, x, y, z);
  setXYZ(this.colorsArray, this.index++, r, g, b);

  const dx = heap[(normalOnB + 0) / 4] * distance;
  const dy = heap[(normalOnB + 4) / 4] * distance;
  const dz = heap[(normalOnB + 8) / 4] * distance;
  setXYZ(this.verticesArray, this.index, x + dx, y + dy, z + dz);
  setXYZ(this.colorsArray, this.index++, r, g, b);
};

AmmoDebugDrawer.prototype.reportErrorWarning = function(warningString) {
  if (Ammo.hasOwnProperty("UTF8ToString")) {
    console.warn(Ammo.UTF8ToString(warningString));
  } else if (!this.warnedOnce) {
    this.warnedOnce = true;
    console.warn("Cannot print warningString, please export UTF8ToString from Ammo.js in make.py");
  }
};

AmmoDebugDrawer.prototype.draw3dText = function(location, textString) {
  //TODO
  console.warn("TODO: draw3dText");
};

AmmoDebugDrawer.prototype.setDebugMode = function(debugMode) {
  this.debugDrawMode = debugMode;
};

AmmoDebugDrawer.prototype.getDebugMode = function() {
  return this.debugDrawMode;
};