/*
* Copyright 2000-2015 JetBrains s.r.o.
*
* 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.
*/
package com.intellij.util.ui;
import com.intellij.openapi.ui.GraphicsConfig;
import com.intellij.util.MethodInvocator;
import com.intellij.util.SystemProperties;
import org.jetbrains.annotations.NotNull;
import javax.swing.*;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.util.Map;
/**
* @author Konstantin Bulenkov
*/
public class GraphicsUtil {
private static final MethodInvocator ourSafelyGetGraphicsMethod = new MethodInvocator(JComponent.class, "safelyGetGraphics", Component.class);
@SuppressWarnings("UndesirableClassUsage")
private static final Graphics2D ourGraphics = new BufferedImage(1,1,BufferedImage.TYPE_INT_ARGB).createGraphics();
static {
setupFractionalMetrics(ourGraphics);
setupAntialiasing(ourGraphics, true, true);
}
public static void setupFractionalMetrics(Graphics g) {
((Graphics2D)g).setRenderingHint(RenderingHints.KEY_FRACTIONALMETRICS, RenderingHints.VALUE_FRACTIONALMETRICS_ON);
}
public static void setupAntialiasing(@NotNull Graphics g2) {
setupAntialiasing(g2, true, false);
}
public static int stringWidth(@NotNull String text, Font font) {
setupAntialiasing(ourGraphics, true, true);
return ourGraphics.getFontMetrics(font).stringWidth(text);
}
public static int charsWidth(char[] data, int off, int len, Font font) {
return ourGraphics.getFontMetrics(font).charsWidth(data, off, len);
}
public static int charWidth(char ch,Font font) {
return ourGraphics.getFontMetrics(font).charWidth(ch);
}
public static int charWidth(int ch,Font font) {
return ourGraphics.getFontMetrics(font).charWidth(ch);
}
public static void setupAntialiasing(Graphics g2, boolean enableAA, boolean ignoreSystemSettings) {
if (g2 instanceof Graphics2D) {
Graphics2D g = (Graphics2D)g2;
Toolkit tk = Toolkit.getDefaultToolkit();
//noinspection HardCodedStringLiteral
Map map = (Map)tk.getDesktopProperty("awt.font.desktophints");
if (map != null && !ignoreSystemSettings) {
g.addRenderingHints(map);
} else {
g.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING,
enableAA ? RenderingHints.VALUE_TEXT_ANTIALIAS_LCD_HBGR : RenderingHints.VALUE_TEXT_ANTIALIAS_OFF);
}
}
}
public static GraphicsConfig setupAAPainting(Graphics g) {
final GraphicsConfig config = new GraphicsConfig(g);
final Graphics2D g2 = (Graphics2D)g;
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
g2.setRenderingHint(RenderingHints.KEY_STROKE_CONTROL, RenderingHints.VALUE_STROKE_NORMALIZE);
return config;
}
public static GraphicsConfig disableAAPainting(Graphics g) {
final GraphicsConfig config = new GraphicsConfig(g);
final Graphics2D g2 = (Graphics2D)g;
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_OFF);
g2.setRenderingHint(RenderingHints.KEY_STROKE_CONTROL, RenderingHints.VALUE_STROKE_DEFAULT);
return config;
}
public static GraphicsConfig paintWithAlpha(Graphics g, float alpha) {
assert 0.0f <= alpha && alpha <= 1.0f : "alpha should be in range 0.0f .. 1.0f";
final GraphicsConfig config = new GraphicsConfig(g);
final Graphics2D g2 = (Graphics2D)g;
g2.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER, alpha));
return config;
}
/**
* Invoking {@link Component#getGraphics()} disables true double buffering withing {@link JRootPane},
* even if no subsequent drawing is actually performed.
* <p>
* This matters only if we use the default {@link RepaintManager} and {@code swing.bufferPerWindow = true}.
* <p>
* True double buffering is needed to eliminate tearing on blit-accelerated scrolling and to restore
* frame buffer content without the usual repainting, even when the EDT is blocked.
* <p>
* As a rule of thumb, you should never invoke neither {@link Component#getGraphics()}
* nor {@link GraphicsUtil#safelyGetGraphics(Component)} unless you really need to perform some drawing.
* <p>
* Under the hood, "getGraphics" is actually "createGraphics" - it creates a new object instance and allocates native resources,
* that should be subsequently released by calling {@link Graphics#dispose()} (called from {@link Graphics#finalize()},
* but there's no need to retain resources unnecessarily).
* <p>
* If you need {@link GraphicsConfiguration}, rely on {@link Component#getGraphicsConfiguration()},
* instead of {@link Graphics2D#getDeviceConfiguration()}.
* <p>
* If you absolutely have to acquire an instance of {@link Graphics}, do that via {@link GraphicsUtil#safelyGetGraphics(Component)}
* and don't forget to invoke {@link Graphics#dispose()} afterwards.
*
* @see JRootPane#disableTrueDoubleBuffering()
* @see JBViewport#isTrueDoubleBufferingAvailableFor(JComponent)
*/
public static Graphics safelyGetGraphics(Component c) {
return SystemProperties.isTrueSmoothScrollingEnabled() && ourSafelyGetGraphicsMethod.isAvailable()
? (Graphics)ourSafelyGetGraphicsMethod.invoke(null, c)
: c.getGraphics();
}
}