/*
* Copyright 2024 The Ray Optics Simulation authors and contributors
*
* 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.
*/
import BaseFilter from '../BaseFilter.js';
import LineObjMixin from '../LineObjMixin.js';
import i18next from 'i18next';
import Simulator from '../../Simulator.js';
import geometry from '../../geometry.js';
import { evaluateLatex } from '../../equation.js';
/**
* Mirror with shape defined by a custom equation.
*
* Tools -> Mirror -> Custom equation
* @class
* @extends BaseFilter
* @memberof sceneObjs
* @property {Point} p1 - The point corresponding to (-1,0) in the coordinate system of the equation.
* @property {Point} p2 - The point corresponding to (1,0) in the coordinate system of the equation.
* @property {string} eqn - The equation of the mirror. The variable is x.
* @property {boolean} filter - Whether it is a dichroic mirror.
* @property {boolean} invert - If true, the ray with wavelength outside the bandwidth is reflected. If false, the ray with wavelength inside the bandwidth is reflected.
* @property {number} wavelength - The target wavelength if dichroic is enabled. The unit is nm.
* @property {number} bandwidth - The bandwidth if dichroic is enabled. The unit is nm.
* @property {Array<Point>} tmp_points - The points on the curve.
* @property {number} tmp_i - The index of the point on the curve where the ray is incident.
*/
class CustomMirror extends LineObjMixin(BaseFilter) {
static type = 'CustomMirror';
static isOptical = true;
static serializableDefaults = {
p1: null,
p2: null,
eqn: "0.5\\cdot\\sqrt{1-x^2}",
filter: false,
invert: false,
wavelength: Simulator.GREEN_WAVELENGTH,
bandwidth: 10
};
populateObjBar(objBar) {
objBar.setTitle(i18next.t('main:tools.categories.mirror'));
objBar.createEquation('y = ', this.eqn, function (obj, value) {
obj.eqn = value;
}, '<ul><li>' + i18next.t('simulator:sceneObjs.common.eqnInfo.constants') + '<br><code>pi e</code></li><li>' + i18next.t('simulator:sceneObjs.common.eqnInfo.operators') + '<br><code>+ - * / ^</code></li><li>' + i18next.t('simulator:sceneObjs.common.eqnInfo.functions') + '<br><code>sqrt sin cos tan sec csc cot sinh cosh tanh log exp arcsin arccos arctan arcsinh arccosh arctanh floor round ceil trunc sgn max min abs</code></li></ul>');
super.populateObjBar(objBar);
}
draw(canvasRenderer, isAboveLight, isHovered) {
const ctx = canvasRenderer.ctx;
const ls = canvasRenderer.lengthScale;
if (this.p1.x == this.p2.x && this.p1.y == this.p2.y) {
ctx.fillStyle = 'rgb(128,128,128)';
ctx.fillRect(this.p1.x - 1.5 * ls, this.p1.y - 1.5 * ls, 3 * ls, 3 * ls);
return;
}
var fn;
try {
fn = evaluateLatex(this.eqn);
} catch (e) {
delete this.tmp_points;
ctx.fillStyle = "red"
ctx.fillRect(this.p1.x - 1.5 * ls, this.p1.y - 1.5 * ls, 3 * ls, 3 * ls);
ctx.fillRect(this.p2.x - 1.5 * ls, this.p2.y - 1.5 * ls, 3 * ls, 3 * ls);
this.error = e.toString();
return;
}
ctx.fillStyle = 'rgb(255,0,255)';
var p12d = geometry.distance(this.p1, this.p2);
// unit vector from p1 to p2
var dir1 = [(this.p2.x - this.p1.x) / p12d, (this.p2.y - this.p1.y) / p12d];
// perpendicular direction
var dir2 = [dir1[1], -dir1[0]];
// get height of (this section of) parabola
var x0 = p12d / 2;
var i;
const colorArray = Simulator.wavelengthToColor(this.wavelength || Simulator.GREEN_WAVELENGTH, 1);
ctx.strokeStyle = isHovered ? 'cyan' : (this.scene.simulateColors && this.wavelength && this.filter ? canvasRenderer.rgbaToCssColor(colorArray) : 'rgb(168,168,168)');
ctx.lineWidth = 1 * ls;
ctx.beginPath();
this.tmp_points = [];
var lastError = "";
for (i = -0.1 * this.scene.lengthScale; i < p12d + 0.09 * this.scene.lengthScale; i += 0.1 * this.scene.lengthScale) {
// avoid using exact integers to avoid problems with detecting intersections
var ix = i + 0.05 * this.scene.lengthScale;
if (ix < 0) ix = 0;
if (ix > p12d) ix = p12d;
var x = ix - x0;
var scaled_x = 2 * x / p12d;
var scaled_y;
try {
scaled_y = fn({ x: scaled_x, "pi": Math.PI });
var y = scaled_y * p12d * 0.5;
var pt = geometry.point(this.p1.x + dir1[0] * ix + dir2[0] * y, this.p1.y + dir1[1] * ix + dir2[1] * y);
if (i == -0.1) {
ctx.moveTo(pt.x, pt.y);
} else {
ctx.lineTo(pt.x, pt.y);
}
this.tmp_points.push(pt);
} catch (e) {
lastError = e;
}
}
if (this.tmp_points.length == 0) {
delete this.tmp_points;
ctx.fillStyle = "red"
ctx.fillRect(this.p1.x - 1.5 * ls, this.p1.y - 1.5 * ls, 3 * ls, 3 * ls);
ctx.fillRect(this.p2.x - 1.5 * ls, this.p2.y - 1.5 * ls, 3 * ls, 3 * ls);
this.error = lastError.toString();
return;
}
ctx.stroke();
if (isHovered) {
ctx.fillStyle = 'rgb(255,0,0)';
ctx.fillRect(this.p1.x - 1.5 * ls, this.p1.y - 1.5 * ls, 3 * ls, 3 * ls);
ctx.fillRect(this.p2.x - 1.5 * ls, this.p2.y - 1.5 * ls, 3 * ls, 3 * ls);
}
this.error = null;
}
checkMouseOver(mouse) {
let dragContext = {};
if (mouse.isOnPoint(this.p1) && geometry.distanceSquared(mouse.pos, this.p1) <= geometry.distanceSquared(mouse.pos, this.p2)) {
dragContext.part = 1;
dragContext.targetPoint = geometry.point(this.p1.x, this.p1.y);
return dragContext;
}
if (mouse.isOnPoint(this.p2)) {
dragContext.part = 2;
dragContext.targetPoint = geometry.point(this.p2.x, this.p2.y);
return dragContext;
}
if (!this.tmp_points) return;
var i;
var pts = this.tmp_points;
for (i = 0; i < pts.length - 1; i++) {
var seg = geometry.line(pts[i], pts[i + 1]);
if (mouse.isOnSegment(seg)) {
// Dragging the entire this
const mousePos = mouse.getPosSnappedToGrid();
dragContext.part = 0;
dragContext.mousePos0 = mousePos; // Mouse position when the user starts dragging
dragContext.mousePos1 = mousePos; // Mouse position at the last moment during dragging
dragContext.snapContext = {};
return dragContext;
}
}
}
checkRayIntersects(ray) {
if (!this.tmp_points || !this.checkRayIntersectFilter(ray)) return;
var i, j;
var pts = this.tmp_points;
var dir = geometry.distance(this.p2, ray.p1) > geometry.distance(this.p1, ray.p1);
var incidentPoint;
for (j = 0; j < pts.length - 1; j++) {
i = dir ? j : (pts.length - 2 - j);
var rp_temp = geometry.linesIntersection(geometry.line(ray.p1, ray.p2), geometry.line(pts[i], pts[i + 1]));
var seg = geometry.line(pts[i], pts[i + 1]);
// need Simulator.MIN_RAY_SEGMENT_LENGTH check to handle a ray that reflects off mirror multiple times
if (geometry.distance(ray.p1, rp_temp) < Simulator.MIN_RAY_SEGMENT_LENGTH * this.scene.lengthScale)
continue;
if (geometry.intersectionIsOnSegment(rp_temp, seg) && geometry.intersectionIsOnRay(rp_temp, ray)) {
if (!incidentPoint || geometry.distance(ray.p1, rp_temp) < geometry.distance(ray.p1, incidentPoint)) {
incidentPoint = rp_temp;
this.tmp_i = i;
}
}
}
if (incidentPoint) return incidentPoint;
}
onRayIncident(ray, rayIndex, incidentPoint) {
var rx = ray.p1.x - incidentPoint.x;
var ry = ray.p1.y - incidentPoint.y;
var i = this.tmp_i;
var pts = this.tmp_points;
var seg = geometry.line(pts[i], pts[i + 1]);
var mx = seg.p2.x - seg.p1.x;
var my = seg.p2.y - seg.p1.y;
ray.p1 = incidentPoint;
var frac;
if (Math.abs(mx) > Math.abs(my)) {
frac = (incidentPoint.x - seg.p1.x) / mx;
} else {
frac = (incidentPoint.y - seg.p1.y) / my;
}
if ((i == 0 && frac < 0.5) || (i == pts.length - 2 && frac >= 0.5)) {
ray.p2 = geometry.point(incidentPoint.x + rx * (my * my - mx * mx) - 2 * ry * mx * my, incidentPoint.y + ry * (mx * mx - my * my) - 2 * rx * mx * my);
} else {
// Use a simple trick to smooth out the slopes of outgoing rays so that image detection works.
// However, a more proper numerical algorithm from the beginning (especially to handle singularities) is still desired.
var outx = incidentPoint.x + rx * (my * my - mx * mx) - 2 * ry * mx * my;
var outy = incidentPoint.y + ry * (mx * mx - my * my) - 2 * rx * mx * my;
var segA;
if (frac < 0.5) {
segA = geometry.line(pts[i - 1], pts[i]);
} else {
segA = geometry.line(pts[i + 1], pts[i + 2]);
}
var rxA = ray.p1.x - incidentPoint.x;
var ryA = ray.p1.y - incidentPoint.y;
var mxA = segA.p2.x - segA.p1.x;
var myA = segA.p2.y - segA.p1.y;
var outxA = incidentPoint.x + rxA * (myA * myA - mxA * mxA) - 2 * ryA * mxA * myA;
var outyA = incidentPoint.y + ryA * (mxA * mxA - myA * myA) - 2 * rxA * mxA * myA;
var outxFinal;
var outyFinal;
if (frac < 0.5) {
outxFinal = outx * (0.5 + frac) + outxA * (0.5 - frac);
outyFinal = outy * (0.5 + frac) + outyA * (0.5 - frac);
} else {
outxFinal = outxA * (frac - 0.5) + outx * (1.5 - frac);
outyFinal = outyA * (frac - 0.5) + outy * (1.5 - frac);
}
//console.log(frac);
ray.p2 = geometry.point(outxFinal, outyFinal);
}
}
};
export default CustomMirror;