Add stretch plumbing
Bug: 179047472
Test: builds & boots
Change-Id: I30b5d6683160af598f98555f61af1cf5a7639bbe
diff --git a/libs/hwui/effects/StretchEffect.cpp b/libs/hwui/effects/StretchEffect.cpp
new file mode 100644
index 0000000..51cbc75
--- /dev/null
+++ b/libs/hwui/effects/StretchEffect.cpp
@@ -0,0 +1,27 @@
+/*
+ * Copyright (C) 2021 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.
+ */
+
+#include "StretchEffect.h"
+
+namespace android::uirenderer {
+
+sk_sp<SkImageFilter> StretchEffect::getImageFilter() const {
+ // TODO: Implement & Cache
+ // Probably need to use mutable to achieve caching
+ return nullptr;
+}
+
+} // namespace android::uirenderer
\ No newline at end of file
diff --git a/libs/hwui/effects/StretchEffect.h b/libs/hwui/effects/StretchEffect.h
new file mode 100644
index 0000000..7dfd639
--- /dev/null
+++ b/libs/hwui/effects/StretchEffect.h
@@ -0,0 +1,66 @@
+/*
+ * Copyright (C) 2021 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.
+ */
+
+#pragma once
+
+#include "utils/MathUtils.h"
+
+#include <SkPoint.h>
+#include <SkRect.h>
+#include <SkImageFilter.h>
+
+namespace android::uirenderer {
+
+// TODO: Inherit from base RenderEffect type?
+class StretchEffect {
+public:
+ enum class StretchInterpolator {
+ SmoothStep,
+ };
+
+ bool isEmpty() const {
+ return MathUtils::isZero(stretchDirection.x())
+ && MathUtils::isZero(stretchDirection.y());
+ }
+
+ void setEmpty() {
+ *this = StretchEffect{};
+ }
+
+ void mergeWith(const StretchEffect& other) {
+ if (other.isEmpty()) {
+ return;
+ }
+ if (isEmpty()) {
+ *this = other;
+ return;
+ }
+ stretchDirection += other.stretchDirection;
+ if (isEmpty()) {
+ return setEmpty();
+ }
+ stretchArea.join(other.stretchArea);
+ maxStretchAmount = std::max(maxStretchAmount, other.maxStretchAmount);
+ }
+
+ sk_sp<SkImageFilter> getImageFilter() const;
+
+ SkRect stretchArea {0, 0, 0, 0};
+ SkVector stretchDirection {0, 0};
+ float maxStretchAmount = 0;
+};
+
+} // namespace android::uirenderer