/*
* Copyright 2000-2017 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.openapi.editor.impl.view;
import com.intellij.openapi.diagnostic.Logger;
import com.intellij.util.ReflectionUtil;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;
import org.jetbrains.annotations.TestOnly;
import sun.font.FontDesignMetrics;
import java.awt.*;
import java.awt.font.FontRenderContext;
import java.awt.font.GlyphVector;
import java.lang.reflect.Method;
/**
* Encapsulates logic related to font metrics. Mock instance can be used in tests to make them independent on font properties on particular
* platform.
*/
public abstract class FontLayoutService {
private static final Logger LOG = Logger.getInstance(FontLayoutService.class);
private static final FontLayoutService DEFAULT_INSTANCE = new DefaultFontLayoutService();
private static FontLayoutService INSTANCE = DEFAULT_INSTANCE;
public static FontLayoutService getInstance() {
return INSTANCE;
}
@NotNull
public abstract GlyphVector layoutGlyphVector(@NotNull Font font, @NotNull FontRenderContext fontRenderContext,
@NotNull char[] chars, int start, int end, boolean isRtl);
public abstract int charWidth(@NotNull FontMetrics fontMetrics, char c);
public abstract int charWidth(@NotNull FontMetrics fontMetrics, int codePoint);
public abstract float charWidth2D(@NotNull FontMetrics fontMetrics, int codePoint);
public abstract int getHeight(@NotNull FontMetrics fontMetrics);
public abstract int getDescent(@NotNull FontMetrics fontMetrics);
@TestOnly
public static void setInstance(@Nullable FontLayoutService fontLayoutService) {
INSTANCE = fontLayoutService == null ? DEFAULT_INSTANCE : fontLayoutService;
}
private static class DefaultFontLayoutService extends FontLayoutService {
// this flag is supported by JetBrains Runtime
private static final int LAYOUT_NO_PAIRED_CHARS_AT_SCRIPT_SPLIT = 8;
private final Method myHandleCharWidthMethod;
private DefaultFontLayoutService() {
myHandleCharWidthMethod = ReflectionUtil.getDeclaredMethod(FontDesignMetrics.class, "handleCharWidth", int.class);
if (myHandleCharWidthMethod == null) {
LOG.warn("Couldn't access FontDesignMetrics.handleCharWidth method");
}
}
@NotNull
@Override
public GlyphVector layoutGlyphVector(@NotNull Font font, @NotNull FontRenderContext fontRenderContext,
@NotNull char[] chars, int start, int end, boolean isRtl) {
return font.layoutGlyphVector(fontRenderContext, chars, start, end, (isRtl ? Font.LAYOUT_RIGHT_TO_LEFT : Font.LAYOUT_LEFT_TO_RIGHT) |
LAYOUT_NO_PAIRED_CHARS_AT_SCRIPT_SPLIT);
}
@Override
public int charWidth(@NotNull FontMetrics fontMetrics, char c) {
return fontMetrics.charWidth(c);
}
@Override
public int charWidth(@NotNull FontMetrics fontMetrics, int codePoint) {
return fontMetrics.charWidth(codePoint);
}
@Override
public float charWidth2D(@NotNull FontMetrics fontMetrics, int codePoint) {
if (myHandleCharWidthMethod != null && fontMetrics instanceof FontDesignMetrics) {
try {
return (float)myHandleCharWidthMethod.invoke(fontMetrics, codePoint);
}
catch (Exception e) {
LOG.debug(e);
}
}
return charWidth(fontMetrics, codePoint);
}
@Override
public int getHeight(@NotNull FontMetrics fontMetrics) {
return fontMetrics.getHeight();
}
@Override
public int getDescent(@NotNull FontMetrics fontMetrics) {
return fontMetrics.getDescent();
}
}
}