Added support for BitmapShader anisotropic filtering
Relnote: "Created new BitmapShader constructor that
enables support for anisotropic filtering."
Bug: 267687306
Test: Added tests to BitmapShaderTest
Change-Id: Ie6e5551f3ae6140dc3afb2d65967b5a6bc08523c
diff --git a/core/api/current.txt b/core/api/current.txt
index fcb3a14..bfdddb5 100644
--- a/core/api/current.txt
+++ b/core/api/current.txt
@@ -14908,7 +14908,9 @@
public class BitmapShader extends android.graphics.Shader {
ctor public BitmapShader(@NonNull android.graphics.Bitmap, @NonNull android.graphics.Shader.TileMode, @NonNull android.graphics.Shader.TileMode);
method public int getFilterMode();
+ method public int getMaxAnisotropy();
method public void setFilterMode(int);
+ method public void setMaxAnisotropy(@IntRange(from=1) int);
field public static final int FILTER_MODE_DEFAULT = 0; // 0x0
field public static final int FILTER_MODE_LINEAR = 2; // 0x2
field public static final int FILTER_MODE_NEAREST = 1; // 0x1
diff --git a/graphics/java/android/graphics/BitmapShader.java b/graphics/java/android/graphics/BitmapShader.java
index 43cb5ee..2f6dd46 100644
--- a/graphics/java/android/graphics/BitmapShader.java
+++ b/graphics/java/android/graphics/BitmapShader.java
@@ -17,6 +17,7 @@
package android.graphics;
import android.annotation.IntDef;
+import android.annotation.IntRange;
import android.annotation.NonNull;
import java.lang.annotation.Retention;
@@ -102,6 +103,8 @@
private boolean mRequestDirectSampling;
+ private int mMaxAniso = 0;
+
/**
* Call this to create a new shader that will draw with a bitmap.
*
@@ -135,15 +138,47 @@
}
/**
- * Set the filter mode to be used when sampling from this shader
+ * Set the filter mode to be used when sampling from this shader. If this is configured
+ * then the anisotropic filtering value specified in any previous call to
+ * {@link #setMaxAnisotropy(int)} is ignored.
*/
public void setFilterMode(@FilterMode int mode) {
if (mode != mFilterMode) {
mFilterMode = mode;
+ mMaxAniso = 0;
discardNativeInstance();
}
}
+ /**
+ * Enables and configures the max anisotropy sampling value. If this value is configured,
+ * {@link #setFilterMode(int)} is ignored.
+ *
+ * Anisotropic filtering can enhance visual quality by removing aliasing effects of images
+ * that are at oblique viewing angles. This value is typically consumed as a power of 2 and
+ * anisotropic values of the next power of 2 typically provide twice the quality improvement
+ * as the previous value. For example, a sampling value of 4 would provide twice the improvement
+ * of a sampling value of 2. It is important to note that higher sampling values reach
+ * diminishing returns as the improvements between 8 and 16 can be slight.
+ *
+ * @param maxAnisotropy The Anisotropy value to use for filtering. Must be greater than 0.
+ */
+ public void setMaxAnisotropy(@IntRange(from = 1) int maxAnisotropy) {
+ if (mMaxAniso != maxAnisotropy && maxAnisotropy > 0) {
+ mMaxAniso = maxAnisotropy;
+ mFilterMode = FILTER_MODE_DEFAULT;
+ discardNativeInstance();
+ }
+ }
+
+ /**
+ * Returns the current max anisotropic filtering value configured by
+ * {@link #setFilterMode(int)}. If {@link #setFilterMode(int)} is invoked this returns zero.
+ */
+ public int getMaxAnisotropy() {
+ return mMaxAniso;
+ }
+
/** @hide */
/* package */ synchronized long getNativeInstanceWithDirectSampling() {
mRequestDirectSampling = true;
@@ -162,8 +197,13 @@
mIsDirectSampled = mRequestDirectSampling;
mRequestDirectSampling = false;
- return nativeCreate(nativeMatrix, mBitmap.getNativeInstance(), mTileX, mTileY,
- enableLinearFilter, mIsDirectSampled);
+ if (mMaxAniso > 0) {
+ return nativeCreateWithMaxAniso(nativeMatrix, mBitmap.getNativeInstance(), mTileX,
+ mTileY, mMaxAniso, mIsDirectSampled);
+ } else {
+ return nativeCreate(nativeMatrix, mBitmap.getNativeInstance(), mTileX, mTileY,
+ enableLinearFilter, mIsDirectSampled);
+ }
}
/** @hide */
@@ -175,5 +215,8 @@
private static native long nativeCreate(long nativeMatrix, long bitmapHandle,
int shaderTileModeX, int shaderTileModeY, boolean filter, boolean isDirectSampled);
+
+ private static native long nativeCreateWithMaxAniso(long nativeMatrix, long bitmapHandle,
+ int shaderTileModeX, int shaderTileModeY, int maxAniso, boolean isDirectSampled);
}
diff --git a/libs/hwui/jni/Shader.cpp b/libs/hwui/jni/Shader.cpp
index fa8e2e7..8a0db1c 100644
--- a/libs/hwui/jni/Shader.cpp
+++ b/libs/hwui/jni/Shader.cpp
@@ -71,11 +71,9 @@
return static_cast<jlong>(reinterpret_cast<uintptr_t>(&Shader_safeUnref));
}
-///////////////////////////////////////////////////////////////////////////////////////////////
-
-static jlong BitmapShader_constructor(JNIEnv* env, jobject o, jlong matrixPtr, jlong bitmapHandle,
- jint tileModeX, jint tileModeY, bool filter,
- bool isDirectSampled) {
+static jlong createBitmapShaderHelper(JNIEnv* env, jobject o, jlong matrixPtr, jlong bitmapHandle,
+ jint tileModeX, jint tileModeY, bool isDirectSampled,
+ const SkSamplingOptions& sampling) {
const SkMatrix* matrix = reinterpret_cast<const SkMatrix*>(matrixPtr);
sk_sp<SkImage> image;
if (bitmapHandle) {
@@ -88,8 +86,7 @@
SkBitmap bitmap;
image = SkMakeImageFromRasterBitmap(bitmap, kNever_SkCopyPixelsMode);
}
- SkSamplingOptions sampling(filter ? SkFilterMode::kLinear : SkFilterMode::kNearest,
- SkMipmapMode::kNone);
+
sk_sp<SkShader> shader;
if (isDirectSampled) {
shader = image->makeRawShader((SkTileMode)tileModeX, (SkTileMode)tileModeY, sampling);
@@ -107,6 +104,26 @@
///////////////////////////////////////////////////////////////////////////////////////////////
+static jlong BitmapShader_constructor(JNIEnv* env, jobject o, jlong matrixPtr, jlong bitmapHandle,
+ jint tileModeX, jint tileModeY, bool filter,
+ bool isDirectSampled) {
+ SkSamplingOptions sampling(filter ? SkFilterMode::kLinear : SkFilterMode::kNearest,
+ SkMipmapMode::kNone);
+ return createBitmapShaderHelper(env, o, matrixPtr, bitmapHandle, tileModeX, tileModeY,
+ isDirectSampled, sampling);
+}
+
+static jlong BitmapShader_constructorWithMaxAniso(JNIEnv* env, jobject o, jlong matrixPtr,
+ jlong bitmapHandle, jint tileModeX,
+ jint tileModeY, jint maxAniso,
+ bool isDirectSampled) {
+ auto sampling = SkSamplingOptions::Aniso(static_cast<int>(maxAniso));
+ return createBitmapShaderHelper(env, o, matrixPtr, bitmapHandle, tileModeX, tileModeY,
+ isDirectSampled, sampling);
+}
+
+///////////////////////////////////////////////////////////////////////////////////////////////
+
static std::vector<SkColor4f> convertColorLongs(JNIEnv* env, jlongArray colorArray) {
const size_t count = env->GetArrayLength(colorArray);
const jlong* colorValues = env->GetLongArrayElements(colorArray, nullptr);
@@ -408,6 +425,8 @@
static const JNINativeMethod gBitmapShaderMethods[] = {
{"nativeCreate", "(JJIIZZ)J", (void*)BitmapShader_constructor},
+ {"nativeCreateWithMaxAniso", "(JJIIIZ)J", (void*)BitmapShader_constructorWithMaxAniso},
+
};
static const JNINativeMethod gLinearGradientMethods[] = {