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A library jar that provides APIs for Applications written for the Google Android Platform.
/*
* Copyright (C) 2006 The Android Open Source Project
*
* 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 android.graphics;
import android.annotation.ColorInt;
import android.annotation.ColorLong;
import android.annotation.NonNull;
import android.annotation.Nullable;
import android.annotation.UnsupportedAppUsage;
import libcore.util.NativeAllocationRegistry;
/**
* Shader is the based class for objects that return horizontal spans of colors
* during drawing. A subclass of Shader is installed in a Paint calling
* paint.setShader(shader). After that any object (other than a bitmap) that is
* drawn with that paint will get its color(s) from the shader.
*/
public class Shader {
private static class NoImagePreloadHolder {
public static final NativeAllocationRegistry sRegistry =
NativeAllocationRegistry.createMalloced(
Shader.class.getClassLoader(), nativeGetFinalizer());
}
/**
* @deprecated Use subclass constructors directly instead.
*/
@Deprecated
public Shader() {
mColorSpace = null;
}
/**
* @hide
*/
public Shader(ColorSpace colorSpace) {
mColorSpace = colorSpace;
if (colorSpace == null) {
throw new IllegalArgumentException(
"Use Shader() to create a Shader with no ColorSpace");
}
// This just ensures that if the ColorSpace is invalid, the Exception will be thrown now.
mColorSpace.getNativeInstance();
}
private final ColorSpace mColorSpace;
/**
* @hide
*/
protected ColorSpace colorSpace() {
return mColorSpace;
}
/**
* Current native shader instance. Created and updated lazily when {@link #getNativeInstance()}
* is called - otherwise may be out of date with java setters/properties.
*/
private long mNativeInstance;
// Runnable to do immediate destruction
private Runnable mCleaner;
/**
* Current matrix - always set to null if local matrix is identity.
*/
private Matrix mLocalMatrix;
public enum TileMode {
/**
* replicate the edge color if the shader draws outside of its
* original bounds
*/
CLAMP (0),
/**
* repeat the shader's image horizontally and vertically
*/
REPEAT (1),
/**
* repeat the shader's image horizontally and vertically, alternating
* mirror images so that adjacent images always seam
*/
MIRROR (2);
TileMode(int nativeInt) {
this.nativeInt = nativeInt;
}
@UnsupportedAppUsage
final int nativeInt;
}
/**
* Return true if the shader has a non-identity local matrix.
* @param localM Set to the local matrix of the shader, if the shader's matrix is non-null.
* @return true if the shader has a non-identity local matrix
*/
public boolean getLocalMatrix(@NonNull Matrix localM) {
if (mLocalMatrix != null) {
localM.set(mLocalMatrix);
return true; // presence of mLocalMatrix means it's not identity
}
return false;
}
/**
* Set the shader's local matrix. Passing null will reset the shader's
* matrix to identity. If the matrix has scale value as 0, the drawing
* result is undefined.
*
* @param localM The shader's new local matrix, or null to specify identity
*/
public void setLocalMatrix(@Nullable Matrix localM) {
if (localM == null || localM.isIdentity()) {
if (mLocalMatrix != null) {
mLocalMatrix = null;
discardNativeInstance();
}
} else {
if (mLocalMatrix == null) {
mLocalMatrix = new Matrix(localM);
discardNativeInstance();
} else if (!mLocalMatrix.equals(localM)) {
mLocalMatrix.set(localM);
discardNativeInstance();
}
}
}
long createNativeInstance(long nativeMatrix) {
return 0;
}
/** @hide */
protected final void discardNativeInstance() {
if (mNativeInstance != 0) {
mCleaner.run();
mCleaner = null;
mNativeInstance = 0;
}
}
/**
* Callback for subclasses to call {@link #discardNativeInstance()} if the most recently
* constructed native instance is no longer valid.
* @hide
*/
protected void verifyNativeInstance() {
}
/**
* @hide
*/
public final long getNativeInstance() {
// verify mNativeInstance is valid
verifyNativeInstance();
if (mNativeInstance == 0) {
mNativeInstance = createNativeInstance(mLocalMatrix == null
? 0 : mLocalMatrix.native_instance);
if (mNativeInstance != 0) {
mCleaner = NoImagePreloadHolder.sRegistry.registerNativeAllocation(
this, mNativeInstance);
}
}
return mNativeInstance;
}
/**
* @hide
*/
public static @ColorLong long[] convertColors(@NonNull @ColorInt int[] colors) {
if (colors.length < 2) {
throw new IllegalArgumentException("needs >= 2 number of colors");
}
long[] colorLongs = new long[colors.length];
for (int i = 0; i < colors.length; ++i) {
colorLongs[i] = Color.pack(colors[i]);
}
return colorLongs;
}
/**
* Detect the ColorSpace that the {@code colors} share.
*
* @throws IllegalArgumentException if the colors do not all share the same,
* valid ColorSpace, or if there are less than 2 colors.
*
* @hide
*/
public static ColorSpace detectColorSpace(@NonNull @ColorLong long[] colors) {
if (colors.length < 2) {
throw new IllegalArgumentException("needs >= 2 number of colors");
}
final ColorSpace colorSpace = Color.colorSpace(colors[0]);
for (int i = 1; i < colors.length; ++i) {
if (Color.colorSpace(colors[i]) != colorSpace) {
throw new IllegalArgumentException("All colors must be in the same ColorSpace!");
}
}
return colorSpace;
}
private static native long nativeGetFinalizer();
}