Java tutorial
/** * * Copyright (C) 2015 - Daniel Hams, Modular Audio Limited * daniel.hams@gmail.com * * Mad 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 3 of the License, or * (at your option) any later version. * * Mad 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 Mad. If not, see <http://www.gnu.org/licenses/>. * */ package uk.co.modularaudio.mads.base.stereo_compressor.ui; import java.awt.Color; import java.awt.Dimension; import java.awt.Graphics; import java.awt.image.BufferedImage; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import uk.co.modularaudio.util.audio.gui.madswingcontrols.PacPanel; import uk.co.modularaudio.util.audio.math.DbToLevelComputer; import uk.co.modularaudio.util.bufferedimage.AllocationBufferType; import uk.co.modularaudio.util.bufferedimage.AllocationLifetime; import uk.co.modularaudio.util.bufferedimage.AllocationMatch; import uk.co.modularaudio.util.bufferedimage.BufferedImageAllocator; import uk.co.modularaudio.util.bufferedimage.TiledBufferedImage; import uk.co.modularaudio.util.exception.DatastoreException; public class AttenuationMeter extends PacPanel { public static final int PREFERRED_WIDTH = 10; public static final int PREFERRED_METER_WIDTH = PREFERRED_WIDTH - 2; private static final Color OVER_THRESHOLD_COLOR = new Color(0.4f, 0.8f, 0.4f); private static final long serialVersionUID = -7723883774839586874L; private static Log log = LogFactory.getLog(AttenuationMeter.class.getName()); private float currentMeterValueDb; private float previouslyPaintedMeterValueDb; private long maxValueTimestamp; private float currentMinValueDb; private float previouslyPaintedMinValueDb; private final StereoCompressorMadUiInstance uiInstance; private final DbToLevelComputer dbToLevelComputer; private final BufferedImageAllocator bufferedImageAllocator; private TiledBufferedImage tiledBufferedImage; private BufferedImage outBufferedImage; private Graphics outBufferedImageGraphics; private int componentWidth = -1; private int componentHeight = -1; public AttenuationMeter(final StereoCompressorMadUiInstance uiInstance, final DbToLevelComputer dbToLevelComputer, final BufferedImageAllocator bia) { setOpaque(true); this.uiInstance = uiInstance; this.dbToLevelComputer = dbToLevelComputer; this.bufferedImageAllocator = bia; setBackground(Color.black); final Dimension myPreferredSize = new Dimension(PREFERRED_WIDTH, 100); this.setPreferredSize(myPreferredSize); } @Override public void paint(final Graphics g) { if (outBufferedImage != null) { g.drawImage(outBufferedImage, 0, 0, null); } } private void refillMeterImage() { // log.debug("Repainting it."); if (outBufferedImageGraphics != null) { outBufferedImageGraphics.setColor(Color.BLACK); outBufferedImageGraphics.fillRect(0, 0, componentWidth, componentHeight); final int meterWidth = PREFERRED_METER_WIDTH; final int totalMeterHeight = componentHeight - 2; final int meterHeight = totalMeterHeight; final int meterHeightOffset = 0; final int yReverser = meterHeight + 1; float levelValue = 0.0f; if (currentMeterValueDb != Float.NEGATIVE_INFINITY) { levelValue = dbToLevelComputer.toNormalisedSliderLevelFromDb(currentMeterValueDb); } outBufferedImageGraphics.setColor(OVER_THRESHOLD_COLOR); final float underVal = levelValue; int underBarHeightInPixels = (int) (underVal * meterHeight); underBarHeightInPixels = underBarHeightInPixels > meterHeight ? meterHeight : underBarHeightInPixels < 0 ? 0 : underBarHeightInPixels; // int underStartY = meterHeight - underBarHeightInPixels + 1 + meterHeightOffset; // outBufferedImageGraphics.fillRect( 3, underStartY, meterWidth - 4, underBarHeightInPixels ); final int underStartY = underBarHeightInPixels + 1 + meterHeightOffset; outBufferedImageGraphics.fillRect(3, 1, meterWidth - 4, meterHeight - underStartY); float minLevelValue = 0.0f; final Color maxDbColor = OVER_THRESHOLD_COLOR; if (currentMinValueDb != Float.NEGATIVE_INFINITY) { minLevelValue = dbToLevelComputer.toNormalisedSliderLevelFromDb(currentMinValueDb); } outBufferedImageGraphics.setColor(maxDbColor); int minValueHeightInPixels = (int) (minLevelValue * meterHeight); minValueHeightInPixels = minValueHeightInPixels > meterHeight ? meterHeight : minValueHeightInPixels < 0 ? 0 : minValueHeightInPixels; final int minStartY = yReverser - minValueHeightInPixels + meterHeightOffset; outBufferedImageGraphics.drawLine(1, minStartY, meterWidth, minStartY); // outBufferedImage.flush(); } } public void receiveDisplayTick(final long currentTime) { final boolean showing = isShowing(); if (currentMeterValueDb < currentMinValueDb) { currentMinValueDb = currentMeterValueDb; maxValueTimestamp = currentTime; } else if (maxValueTimestamp + uiInstance.framesBetweenPeakReset < currentTime) { currentMinValueDb = currentMeterValueDb; maxValueTimestamp = currentTime; } if (showing) { if (currentMeterValueDb != previouslyPaintedMeterValueDb || currentMinValueDb != previouslyPaintedMinValueDb) { refillMeterImage(); repaint(); previouslyPaintedMeterValueDb = currentMeterValueDb; previouslyPaintedMinValueDb = currentMinValueDb; } } } public void receiveMeterReadingInDb(final long currentFrameTime, final float meterReadingDb) { currentMeterValueDb = meterReadingDb; } public void destroy() { if (tiledBufferedImage != null) { try { bufferedImageAllocator.freeBufferedImage(tiledBufferedImage); } catch (final Exception e) { final String msg = "Failed to free up allocated image: " + e.toString(); log.error(msg); } tiledBufferedImage = null; outBufferedImage = null; outBufferedImageGraphics = null; } } @Override public void setBounds(final int x, final int y, final int width, final int height) { super.setBounds(x, y, width, height); try { if (tiledBufferedImage != null) { bufferedImageAllocator.freeBufferedImage(tiledBufferedImage); } final AllocationMatch myAllocationMatch = new AllocationMatch(); tiledBufferedImage = bufferedImageAllocator.allocateBufferedImage("AttenuationMeter", myAllocationMatch, AllocationLifetime.SHORT, AllocationBufferType.TYPE_INT_RGB, width, height); outBufferedImage = tiledBufferedImage.getUnderlyingBufferedImage(); outBufferedImageGraphics = outBufferedImage.createGraphics(); outBufferedImageGraphics.setColor(Color.BLACK); outBufferedImageGraphics.fillRect(0, 0, componentWidth, componentHeight); } catch (final DatastoreException e) { if (log.isErrorEnabled()) { log.error("DatastoreException caught allocating buffered image: " + e.toString(), e); } } componentWidth = width; componentHeight = height; } }