[CE] Extract transform computation logic to ProjectionSpace
The logic that computes the transformation matrix that maps
from one projection space to another currently lives in
DisplayDevice::setProjection although it's not specific to
the DisplayDevice. In this CL we move this to ProjectionSpace
so it can be reused and add appropriate testing. Additionally
we move most of the remaining logic from DisplayDevice::setProjection
to Output::setProjection.
Bug: 161793589
Bug: 165184567
Test: atest ProjectionSpaceTest
Test: atest libcompositionengine_test libsurfaceflinger_unittest
Test: on phone emualutor test that rotation works propertly
Change-Id: Ic65a3ba18eda597edb7d2c8635cccfa7cb58a107
diff --git a/services/surfaceflinger/CompositionEngine/tests/ProjectionSpaceTest.cpp b/services/surfaceflinger/CompositionEngine/tests/ProjectionSpaceTest.cpp
new file mode 100644
index 0000000..704f5a8
--- /dev/null
+++ b/services/surfaceflinger/CompositionEngine/tests/ProjectionSpaceTest.cpp
@@ -0,0 +1,144 @@
+/*
+ * Copyright 2020 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 <compositionengine/ProjectionSpace.h>
+#include <gtest/gtest.h>
+
+namespace android::compositionengine {
+namespace {
+
+// Returns a rectangular strip along the side of the given rect pointed by
+// rotation. E.g. if rotation is ROTATION_0, the srip will be along the top
+// side, if it is ROTATION_90 the stip will be along the right wall.
+// One of the dimensions of the strip will be 0 and the other one will match
+// the length of the corresponding side.
+// The strip will be contained inside the given rect.
+Rect getSideStrip(const Rect& rect, ui::Rotation rotation) {
+ int width, height;
+ if (rotation == ui::ROTATION_90 || rotation == ui::ROTATION_270) {
+ width = 0;
+ height = rect.height();
+ } else {
+ width = rect.width();
+ height = 0;
+ }
+
+ if (rotation == ui::ROTATION_0 || rotation == ui::ROTATION_270) {
+ return Rect(rect.left, rect.top, rect.left + width, rect.top + height);
+ }
+
+ if (rotation == ui::ROTATION_90) {
+ return Rect(rect.right, rect.top, rect.right + width, rect.top + height);
+ }
+
+ if (rotation == ui::ROTATION_180) {
+ return Rect(rect.left, rect.bottom, rect.left + width, rect.bottom + height);
+ }
+
+ return Rect::INVALID_RECT;
+}
+} // namespace
+
+TEST(ProjectionSpaceTest, getTransformToSelfIsIdentity) {
+ ProjectionSpace space;
+ space.content = Rect(100, 200);
+ space.bounds = Rect(100, 200);
+
+ const ui::Transform identity;
+ for (int rotation = 0; rotation <= 3; rotation++) {
+ space.orientation = ui::Rotation(rotation);
+ EXPECT_EQ(space.getTransform(space), identity);
+ }
+}
+
+TEST(ProjectionSpaceTest, getTransformWhenTranslationIsNeeded) {
+ ProjectionSpace source;
+ source.content = Rect(10, 10, 20, 20);
+ source.bounds = Rect(100, 200);
+
+ ProjectionSpace dest;
+ dest.content = Rect(10, 20, 30, 20);
+ dest.bounds = source.bounds;
+
+ const auto transform = source.getTransform(dest);
+ EXPECT_EQ(transform.transform(source.content), dest.content);
+}
+
+TEST(ProjectionSpaceTest, getTransformWhenScaleIsNeeded) {
+ ProjectionSpace source;
+ source.content = Rect(0, 0, 20, 20);
+ source.bounds = Rect(100, 200);
+
+ ProjectionSpace dest;
+ dest.content = Rect(0, 0, 40, 30);
+ dest.bounds = source.bounds;
+
+ const auto transform = source.getTransform(dest);
+ EXPECT_EQ(transform.transform(source.content), dest.content);
+}
+
+TEST(ProjectionSpaceTest, getSideStripTest) {
+ const Rect rect(10, 20, 40, 100);
+ EXPECT_EQ(getSideStrip(rect, ui::ROTATION_0), Rect(10, 20, 40, 20));
+ EXPECT_EQ(getSideStrip(rect, ui::ROTATION_90), Rect(40, 20, 40, 100));
+ EXPECT_EQ(getSideStrip(rect, ui::ROTATION_180), Rect(10, 100, 40, 100));
+ EXPECT_EQ(getSideStrip(rect, ui::ROTATION_270), Rect(10, 20, 10, 100));
+}
+
+void testTransform(const ProjectionSpace& source, const ProjectionSpace& dest) {
+ const auto transform = source.getTransform(dest);
+ EXPECT_EQ(transform.transform(source.content), dest.content)
+ << "Source content doesn't map to dest content when projecting " << to_string(source)
+ << " onto " << to_string(dest);
+
+ // We take a strip at the top (according to the orientation) of each
+ // content rect and verify that transform maps between them. This way we
+ // verify that the transform is rotating properly.
+ // In the following example the strip is marked with asterisks:
+ //
+ // ******* +-------*
+ // | | | *
+ // | | | *
+ // +-----+ +-------*
+ // source(ROTATION_0) dest (ROTATION_90)
+ const auto sourceStrip = getSideStrip(source.content, source.orientation);
+ const auto destStrip = getSideStrip(dest.content, dest.orientation);
+ ASSERT_NE(sourceStrip, Rect::INVALID_RECT);
+ ASSERT_NE(destStrip, Rect::INVALID_RECT);
+ const auto mappedStrip = transform.transform(sourceStrip);
+ EXPECT_EQ(mappedStrip, destStrip)
+ << to_string(sourceStrip) << " maps to " << to_string(mappedStrip) << " instead of "
+ << to_string(destStrip) << " when projecting " << to_string(source) << " onto "
+ << to_string(dest);
+}
+
+TEST(ProjectionSpaceTest, getTransformWithOrienations) {
+ ProjectionSpace source;
+ source.bounds = Rect(12, 13, 678, 789);
+ source.content = Rect(40, 50, 234, 343);
+ ProjectionSpace dest;
+ dest.bounds = Rect(17, 18, 879, 564);
+ dest.content = Rect(43, 52, 432, 213);
+
+ for (int sourceRot = 0; sourceRot <= 3; sourceRot++) {
+ source.orientation = ui::Rotation(sourceRot);
+ for (int destRot = 0; destRot <= 3; destRot++) {
+ dest.orientation = ui::Rotation(destRot);
+ testTransform(source, dest);
+ }
+ }
+}
+
+} // namespace android::compositionengine