Java tutorial
/* Copyright (C) Paul Falstad and Iain Sharp This file is part of CircuitJS1. CircuitJS1 is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 2 of the License, or (at your option) any later version. CircuitJS1 is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with CircuitJS1. If not, see <http://www.gnu.org/licenses/>. */ package com.lushprojects.circuitjs1.client; import com.google.gwt.user.client.Window; //import java.awt.*; //import java.util.StringTokenizer; class VoltageElm extends CircuitElm { static final int FLAG_COS = 2; static final int FLAG_PULSE_DUTY = 4; int waveform; static final int WF_DC = 0; static final int WF_AC = 1; static final int WF_SQUARE = 2; static final int WF_TRIANGLE = 3; static final int WF_SAWTOOTH = 4; static final int WF_PULSE = 5; static final int WF_VAR = 6; double frequency, maxVoltage, freqTimeZero, bias, phaseShift, dutyCycle; static final double defaultPulseDuty = 1 / (2 * Math.PI); VoltageElm(int xx, int yy, int wf) { super(xx, yy); waveform = wf; maxVoltage = 5; frequency = 40; dutyCycle = .5; reset(); } public VoltageElm(int xa, int ya, int xb, int yb, int f, StringTokenizer st) { super(xa, ya, xb, yb, f); maxVoltage = 5; frequency = 40; waveform = WF_DC; dutyCycle = .5; try { waveform = new Integer(st.nextToken()).intValue(); frequency = new Double(st.nextToken()).doubleValue(); maxVoltage = new Double(st.nextToken()).doubleValue(); bias = new Double(st.nextToken()).doubleValue(); phaseShift = new Double(st.nextToken()).doubleValue(); dutyCycle = new Double(st.nextToken()).doubleValue(); } catch (Exception e) { } if ((flags & FLAG_COS) != 0) { flags &= ~FLAG_COS; phaseShift = pi / 2; } // old circuit files have the wrong duty cycle for pulse waveforms (wasn't configurable in the past) if ((flags & FLAG_PULSE_DUTY) == 0 && waveform == WF_PULSE) { dutyCycle = defaultPulseDuty; } reset(); } int getDumpType() { return 'v'; } String dump() { // set flag so we know if duty cycle is correct for pulse waveforms if (waveform == WF_PULSE) flags |= FLAG_PULSE_DUTY; else flags &= ~FLAG_PULSE_DUTY; return super.dump() + " " + waveform + " " + frequency + " " + maxVoltage + " " + bias + " " + phaseShift + " " + dutyCycle; // VarRailElm adds text at the end } void reset() { freqTimeZero = 0; curcount = 0; } double triangleFunc(double x) { if (x < pi) return x * (2 / pi) - 1; return 1 - (x - pi) * (2 / pi); } void stamp() { if (waveform == WF_DC) sim.stampVoltageSource(nodes[0], nodes[1], voltSource, getVoltage()); else sim.stampVoltageSource(nodes[0], nodes[1], voltSource); } void doStep() { if (waveform != WF_DC) sim.updateVoltageSource(nodes[0], nodes[1], voltSource, getVoltage()); } double getVoltage() { double w = 2 * pi * (sim.t - freqTimeZero) * frequency + phaseShift; switch (waveform) { case WF_DC: return maxVoltage + bias; case WF_AC: return Math.sin(w) * maxVoltage + bias; case WF_SQUARE: return bias + ((w % (2 * pi) > (2 * pi * dutyCycle)) ? -maxVoltage : maxVoltage); case WF_TRIANGLE: return bias + triangleFunc(w % (2 * pi)) * maxVoltage; case WF_SAWTOOTH: return bias + (w % (2 * pi)) * (maxVoltage / pi) - maxVoltage; case WF_PULSE: return ((w % (2 * pi)) < (2 * pi * dutyCycle)) ? maxVoltage + bias : bias; default: return 0; } } final int circleSize = 17; void setPoints() { super.setPoints(); calcLeads((waveform == WF_DC || waveform == WF_VAR) ? 8 : circleSize * 2); } void draw(Graphics g) { setBbox(x, y, x2, y2); draw2Leads(g); if (waveform == WF_DC) { setPowerColor(g, false); setVoltageColor(g, volts[0]); interpPoint2(lead1, lead2, ps1, ps2, 0, 10); drawThickLine(g, ps1, ps2); setVoltageColor(g, volts[1]); int hs = 16; setBbox(point1, point2, hs); interpPoint2(lead1, lead2, ps1, ps2, 1, hs); drawThickLine(g, ps1, ps2); } else { setBbox(point1, point2, circleSize); interpPoint(lead1, lead2, ps1, .5); drawWaveform(g, ps1); if (bias != 0) { g.setColor(Color.white); g.setFont(unitsFont); Point plusPoint = interpPoint(point1, point2, (dn / 2 + circleSize + 4) / dn, 10 * dsign); plusPoint.y += 4; int w = (int) g.context.measureText("+").getWidth(); ; g.drawString("+", plusPoint.x - w / 2, plusPoint.y); } } updateDotCount(); if (sim.dragElm != this) { if (waveform == WF_DC) drawDots(g, point1, point2, curcount); else { drawDots(g, point1, lead1, curcount); drawDots(g, point2, lead2, -curcount); } } drawPosts(g); } void drawWaveform(Graphics g, Point center) { g.setColor(needsHighlight() ? selectColor : Color.gray); setPowerColor(g, false); int xc = center.x; int yc = center.y; drawThickCircle(g, xc, yc, circleSize); int wl = 8; adjustBbox(xc - circleSize, yc - circleSize, xc + circleSize, yc + circleSize); int xc2; switch (waveform) { case WF_DC: { break; } case WF_SQUARE: xc2 = (int) (wl * 2 * dutyCycle - wl + xc); xc2 = max(xc - wl + 3, min(xc + wl - 3, xc2)); drawThickLine(g, xc - wl, yc - wl, xc - wl, yc); drawThickLine(g, xc - wl, yc - wl, xc2, yc - wl); drawThickLine(g, xc2, yc - wl, xc2, yc + wl); drawThickLine(g, xc + wl, yc + wl, xc2, yc + wl); drawThickLine(g, xc + wl, yc, xc + wl, yc + wl); break; case WF_PULSE: yc += wl / 2; drawThickLine(g, xc - wl, yc - wl, xc - wl, yc); drawThickLine(g, xc - wl, yc - wl, xc - wl / 2, yc - wl); drawThickLine(g, xc - wl / 2, yc - wl, xc - wl / 2, yc); drawThickLine(g, xc - wl / 2, yc, xc + wl, yc); break; case WF_SAWTOOTH: drawThickLine(g, xc, yc - wl, xc - wl, yc); drawThickLine(g, xc, yc - wl, xc, yc + wl); drawThickLine(g, xc, yc + wl, xc + wl, yc); break; case WF_TRIANGLE: { int xl = 5; drawThickLine(g, xc - xl * 2, yc, xc - xl, yc - wl); drawThickLine(g, xc - xl, yc - wl, xc, yc); drawThickLine(g, xc, yc, xc + xl, yc + wl); drawThickLine(g, xc + xl, yc + wl, xc + xl * 2, yc); break; } case WF_AC: { int i; int xl = 10; g.context.beginPath(); g.context.setLineWidth(3.0); for (i = -xl; i <= xl; i++) { int yy = yc + (int) (.95 * Math.sin(i * pi / xl) * wl); if (i == -xl) g.context.moveTo(xc + i, yy); else g.context.lineTo(xc + i, yy); } g.context.stroke(); g.context.setLineWidth(1.0); break; } } if (sim.showValuesCheckItem.getState()) { String s = getShortUnitText(frequency, "Hz"); if (dx == 0 || dy == 0) drawValues(g, s, circleSize); } } int getVoltageSourceCount() { return 1; } double getPower() { return -getVoltageDiff() * current; } double getVoltageDiff() { return volts[1] - volts[0]; } void getInfo(String arr[]) { switch (waveform) { case WF_DC: case WF_VAR: arr[0] = "voltage source"; break; case WF_AC: arr[0] = "A/C source"; break; case WF_SQUARE: arr[0] = "square wave gen"; break; case WF_PULSE: arr[0] = "pulse gen"; break; case WF_SAWTOOTH: arr[0] = "sawtooth gen"; break; case WF_TRIANGLE: arr[0] = "triangle gen"; break; } arr[1] = "I = " + getCurrentText(getCurrent()); arr[2] = ((this instanceof RailElm) ? "V = " : "Vd = ") + getVoltageText(getVoltageDiff()); if (waveform != WF_DC && waveform != WF_VAR) { arr[3] = "f = " + getUnitText(frequency, "Hz"); arr[4] = "Vmax = " + getVoltageText(maxVoltage); int i = 5; if (waveform == WF_AC && bias == 0) arr[i++] = "V(rms) = " + getVoltageText(maxVoltage / 1.41421356); if (bias != 0) arr[i++] = "Voff = " + getVoltageText(bias); else if (frequency > 500) arr[i++] = "wavelength = " + getUnitText(2.9979e8 / frequency, "m"); arr[i++] = "P = " + getUnitText(getPower(), "W"); } if (waveform == WF_DC && current != 0 && sim.showResistanceInVoltageSources) { arr[3] = "(R = " + getUnitText(maxVoltage / current, sim.ohmString) + ")"; } } public EditInfo getEditInfo(int n) { if (n == 0) return new EditInfo(waveform == WF_DC ? "Voltage" : "Max Voltage", maxVoltage, -20, 20); if (n == 1) { EditInfo ei = new EditInfo("Waveform", waveform, -1, -1); ei.choice = new Choice(); ei.choice.add("D/C"); ei.choice.add("A/C"); ei.choice.add("Square Wave"); ei.choice.add("Triangle"); ei.choice.add("Sawtooth"); ei.choice.add("Pulse"); ei.choice.select(waveform); return ei; } if (waveform == WF_DC) return null; if (n == 2) return new EditInfo("Frequency (Hz)", frequency, 4, 500); if (n == 3) return new EditInfo("DC Offset (V)", bias, -20, 20); if (n == 4) return new EditInfo("Phase Offset (degrees)", phaseShift * 180 / pi, -180, 180).setDimensionless(); if (n == 5 && (waveform == WF_PULSE || waveform == WF_SQUARE)) return new EditInfo("Duty Cycle", dutyCycle * 100, 0, 100).setDimensionless(); return null; } public void setEditValue(int n, EditInfo ei) { if (n == 0) maxVoltage = ei.value; if (n == 3) bias = ei.value; if (n == 2) { // adjust time zero to maintain continuity ind the waveform // even though the frequency has changed. double oldfreq = frequency; frequency = ei.value; double maxfreq = 1 / (8 * sim.timeStep); if (frequency > maxfreq) { if (Window.confirm("Adjust timestep to allow for higher frequencies?")) sim.timeStep = 1 / (32 * frequency); else frequency = maxfreq; } double adj = frequency - oldfreq; freqTimeZero = sim.t - oldfreq * (sim.t - freqTimeZero) / frequency; } if (n == 1) { int ow = waveform; waveform = ei.choice.getSelectedIndex(); if (waveform == WF_DC && ow != WF_DC) { ei.newDialog = true; bias = 0; } else if (waveform != ow) ei.newDialog = true; // change duty cycle if we're changing to or from pulse if (waveform == WF_PULSE && ow != WF_PULSE) dutyCycle = defaultPulseDuty; else if (ow == WF_PULSE && waveform != WF_PULSE) dutyCycle = .5; setPoints(); } if (n == 4) phaseShift = ei.value * pi / 180; if (n == 5) dutyCycle = ei.value * .01; } }