SF: Split FE and CE

Make LayerFE a standalone class with no links back to Layer. Pass
LayerSnapshot from Layer into LayerFE before CompositionEngine::present
and back after.

Bug: 238781169
Test: go/wm-smoke
Test: presubmit

Change-Id: I5395fb717a931f88e2bf26395acd21e8b308961e
diff --git a/services/surfaceflinger/LayerFE.cpp b/services/surfaceflinger/LayerFE.cpp
new file mode 100644
index 0000000..3bdb521
--- /dev/null
+++ b/services/surfaceflinger/LayerFE.cpp
@@ -0,0 +1,386 @@
+/*
+ * Copyright 2022 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.
+ */
+
+// #define LOG_NDEBUG 0
+#undef LOG_TAG
+#define LOG_TAG "LayerFE"
+#define ATRACE_TAG ATRACE_TAG_GRAPHICS
+
+#include <gui/GLConsumer.h>
+#include <gui/TraceUtils.h>
+#include <math/vec3.h>
+#include <system/window.h>
+#include <utils/Log.h>
+
+#include "DisplayDevice.h"
+#include "LayerFE.h"
+
+namespace android {
+
+namespace {
+constexpr float defaultMaxLuminance = 1000.0;
+
+constexpr mat4 inverseOrientation(uint32_t transform) {
+    const mat4 flipH(-1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 1);
+    const mat4 flipV(1, 0, 0, 0, 0, -1, 0, 0, 0, 0, 1, 0, 0, 1, 0, 1);
+    const mat4 rot90(0, 1, 0, 0, -1, 0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 1);
+    mat4 tr;
+
+    if (transform & NATIVE_WINDOW_TRANSFORM_ROT_90) {
+        tr = tr * rot90;
+    }
+    if (transform & NATIVE_WINDOW_TRANSFORM_FLIP_H) {
+        tr = tr * flipH;
+    }
+    if (transform & NATIVE_WINDOW_TRANSFORM_FLIP_V) {
+        tr = tr * flipV;
+    }
+    return inverse(tr);
+}
+
+FloatRect reduce(const FloatRect& win, const Region& exclude) {
+    if (CC_LIKELY(exclude.isEmpty())) {
+        return win;
+    }
+    // Convert through Rect (by rounding) for lack of FloatRegion
+    return Region(Rect{win}).subtract(exclude).getBounds().toFloatRect();
+}
+
+// Computes the transform matrix using the setFilteringEnabled to determine whether the
+// transform matrix should be computed for use with bilinear filtering.
+void getDrawingTransformMatrix(const std::shared_ptr<renderengine::ExternalTexture>& buffer,
+                               Rect bufferCrop, uint32_t bufferTransform, bool filteringEnabled,
+                               float outMatrix[16]) {
+    if (!buffer) {
+        ALOGE("Buffer should not be null!");
+        return;
+    }
+    GLConsumer::computeTransformMatrix(outMatrix, static_cast<float>(buffer->getWidth()),
+                                       static_cast<float>(buffer->getHeight()),
+                                       buffer->getPixelFormat(), bufferCrop, bufferTransform,
+                                       filteringEnabled);
+}
+
+} // namespace
+
+LayerFE::LayerFE(const std::string& name) : mName(name) {}
+
+const compositionengine::LayerFECompositionState* LayerFE::getCompositionState() const {
+    return mSnapshot.get();
+}
+
+bool LayerFE::onPreComposition(nsecs_t refreshStartTime, bool) {
+    mCompositionResult.refreshStartTime = refreshStartTime;
+    return mSnapshot->hasReadyFrame;
+}
+
+std::optional<compositionengine::LayerFE::LayerSettings> LayerFE::prepareClientComposition(
+        compositionengine::LayerFE::ClientCompositionTargetSettings& targetSettings) const {
+    std::optional<compositionengine::LayerFE::LayerSettings> layerSettings =
+            prepareClientCompositionInternal(targetSettings);
+    // Nothing to render.
+    if (!layerSettings) {
+        return {};
+    }
+
+    // HWC requests to clear this layer.
+    if (targetSettings.clearContent) {
+        prepareClearClientComposition(*layerSettings, false /* blackout */);
+        return layerSettings;
+    }
+
+    // set the shadow for the layer if needed
+    prepareShadowClientComposition(*layerSettings, targetSettings.viewport);
+
+    return layerSettings;
+}
+
+std::optional<compositionengine::LayerFE::LayerSettings> LayerFE::prepareClientCompositionInternal(
+        compositionengine::LayerFE::ClientCompositionTargetSettings& targetSettings) const {
+    ATRACE_CALL();
+    compositionengine::LayerFE::LayerSettings layerSettings;
+    layerSettings.geometry.boundaries =
+            reduce(mSnapshot->geomLayerBounds, mSnapshot->transparentRegionHint);
+    layerSettings.geometry.positionTransform = mSnapshot->geomLayerTransform.asMatrix4();
+
+    // skip drawing content if the targetSettings indicate the content will be occluded
+    const bool drawContent = targetSettings.realContentIsVisible || targetSettings.clearContent;
+    layerSettings.skipContentDraw = !drawContent;
+
+    if (!mSnapshot->colorTransformIsIdentity) {
+        layerSettings.colorTransform = mSnapshot->colorTransform;
+    }
+
+    const auto& roundedCornerState = mSnapshot->roundedCorner;
+    layerSettings.geometry.roundedCornersRadius = roundedCornerState.radius;
+    layerSettings.geometry.roundedCornersCrop = roundedCornerState.cropRect;
+
+    layerSettings.alpha = mSnapshot->alpha;
+    layerSettings.sourceDataspace = mSnapshot->dataspace;
+
+    // Override the dataspace transfer from 170M to sRGB if the device configuration requests this.
+    // We do this here instead of in buffer info so that dumpsys can still report layers that are
+    // using the 170M transfer.
+    if (targetSettings.treat170mAsSrgb &&
+        (layerSettings.sourceDataspace & HAL_DATASPACE_TRANSFER_MASK) ==
+                HAL_DATASPACE_TRANSFER_SMPTE_170M) {
+        layerSettings.sourceDataspace = static_cast<ui::Dataspace>(
+                (layerSettings.sourceDataspace & HAL_DATASPACE_STANDARD_MASK) |
+                (layerSettings.sourceDataspace & HAL_DATASPACE_RANGE_MASK) |
+                HAL_DATASPACE_TRANSFER_SRGB);
+    }
+
+    layerSettings.whitePointNits = targetSettings.whitePointNits;
+    switch (targetSettings.blurSetting) {
+        case LayerFE::ClientCompositionTargetSettings::BlurSetting::Enabled:
+            layerSettings.backgroundBlurRadius = mSnapshot->backgroundBlurRadius;
+            layerSettings.blurRegions = mSnapshot->blurRegions;
+            layerSettings.blurRegionTransform = mSnapshot->geomInverseLayerTransform.asMatrix4();
+            break;
+        case LayerFE::ClientCompositionTargetSettings::BlurSetting::BackgroundBlurOnly:
+            layerSettings.backgroundBlurRadius = mSnapshot->backgroundBlurRadius;
+            break;
+        case LayerFE::ClientCompositionTargetSettings::BlurSetting::BlurRegionsOnly:
+            layerSettings.blurRegions = mSnapshot->blurRegions;
+            layerSettings.blurRegionTransform = mSnapshot->geomInverseLayerTransform.asMatrix4();
+            break;
+        case LayerFE::ClientCompositionTargetSettings::BlurSetting::Disabled:
+        default:
+            break;
+    }
+    layerSettings.stretchEffect = mSnapshot->stretchEffect;
+    // Record the name of the layer for debugging further down the stack.
+    layerSettings.name = mSnapshot->name;
+
+    if (hasEffect() && !hasBufferOrSidebandStream()) {
+        prepareEffectsClientComposition(layerSettings, targetSettings);
+        return layerSettings;
+    }
+
+    prepareBufferStateClientComposition(layerSettings, targetSettings);
+    return layerSettings;
+}
+
+void LayerFE::prepareClearClientComposition(LayerFE::LayerSettings& layerSettings,
+                                            bool blackout) const {
+    layerSettings.source.buffer.buffer = nullptr;
+    layerSettings.source.solidColor = half3(0.0f, 0.0f, 0.0f);
+    layerSettings.disableBlending = true;
+    layerSettings.bufferId = 0;
+    layerSettings.frameNumber = 0;
+
+    // If layer is blacked out, force alpha to 1 so that we draw a black color layer.
+    layerSettings.alpha = blackout ? 1.0f : 0.0f;
+    layerSettings.name = mSnapshot->name;
+}
+
+void LayerFE::prepareEffectsClientComposition(
+        compositionengine::LayerFE::LayerSettings& layerSettings,
+        compositionengine::LayerFE::ClientCompositionTargetSettings& targetSettings) const {
+    // If fill bounds are occluded or the fill color is invalid skip the fill settings.
+    if (targetSettings.realContentIsVisible && fillsColor()) {
+        // Set color for color fill settings.
+        layerSettings.source.solidColor = mSnapshot->color.rgb;
+    } else if (hasBlur() || drawShadows()) {
+        layerSettings.skipContentDraw = true;
+    }
+}
+
+void LayerFE::prepareBufferStateClientComposition(
+        compositionengine::LayerFE::LayerSettings& layerSettings,
+        compositionengine::LayerFE::ClientCompositionTargetSettings& targetSettings) const {
+    ATRACE_CALL();
+    if (CC_UNLIKELY(!mSnapshot->externalTexture)) {
+        // If there is no buffer for the layer or we have sidebandstream where there is no
+        // activeBuffer, then we need to return LayerSettings.
+        return;
+    }
+    const bool blackOutLayer =
+            (mSnapshot->hasProtectedContent && !targetSettings.supportsProtectedContent) ||
+            ((mSnapshot->isSecure || mSnapshot->hasProtectedContent) && !targetSettings.isSecure);
+    const bool bufferCanBeUsedAsHwTexture =
+            mSnapshot->externalTexture->getUsage() & GraphicBuffer::USAGE_HW_TEXTURE;
+    if (blackOutLayer || !bufferCanBeUsedAsHwTexture) {
+        ALOGE_IF(!bufferCanBeUsedAsHwTexture, "%s is blacked out as buffer is not gpu readable",
+                 mSnapshot->name.c_str());
+        prepareClearClientComposition(layerSettings, true /* blackout */);
+        return;
+    }
+
+    layerSettings.source.buffer.buffer = mSnapshot->externalTexture;
+    layerSettings.source.buffer.isOpaque = mSnapshot->contentOpaque;
+    layerSettings.source.buffer.fence = mSnapshot->acquireFence;
+    layerSettings.source.buffer.textureName = mSnapshot->textureName;
+    layerSettings.source.buffer.usePremultipliedAlpha = mSnapshot->premultipliedAlpha;
+    layerSettings.source.buffer.isY410BT2020 = mSnapshot->isHdrY410;
+    bool hasSmpte2086 = mSnapshot->hdrMetadata.validTypes & HdrMetadata::SMPTE2086;
+    bool hasCta861_3 = mSnapshot->hdrMetadata.validTypes & HdrMetadata::CTA861_3;
+    float maxLuminance = 0.f;
+    if (hasSmpte2086 && hasCta861_3) {
+        maxLuminance = std::min(mSnapshot->hdrMetadata.smpte2086.maxLuminance,
+                                mSnapshot->hdrMetadata.cta8613.maxContentLightLevel);
+    } else if (hasSmpte2086) {
+        maxLuminance = mSnapshot->hdrMetadata.smpte2086.maxLuminance;
+    } else if (hasCta861_3) {
+        maxLuminance = mSnapshot->hdrMetadata.cta8613.maxContentLightLevel;
+    } else {
+        switch (layerSettings.sourceDataspace & HAL_DATASPACE_TRANSFER_MASK) {
+            case HAL_DATASPACE_TRANSFER_ST2084:
+            case HAL_DATASPACE_TRANSFER_HLG:
+                // Behavior-match previous releases for HDR content
+                maxLuminance = defaultMaxLuminance;
+                break;
+        }
+    }
+    layerSettings.source.buffer.maxLuminanceNits = maxLuminance;
+    layerSettings.frameNumber = mSnapshot->frameNumber;
+    layerSettings.bufferId = mSnapshot->externalTexture->getId();
+
+    const bool useFiltering = targetSettings.needsFiltering ||
+            mSnapshot->geomLayerTransform.needsBilinearFiltering() ||
+            mSnapshot->bufferNeedsFiltering;
+
+    // Query the texture matrix given our current filtering mode.
+    float textureMatrix[16];
+    getDrawingTransformMatrix(layerSettings.source.buffer.buffer, mSnapshot->geomContentCrop,
+                              mSnapshot->geomBufferTransform, useFiltering, textureMatrix);
+
+    if (mSnapshot->geomBufferUsesDisplayInverseTransform) {
+        /*
+         * the code below applies the primary display's inverse transform to
+         * the texture transform
+         */
+        uint32_t transform = DisplayDevice::getPrimaryDisplayRotationFlags();
+        mat4 tr = inverseOrientation(transform);
+
+        /**
+         * TODO(b/36727915): This is basically a hack.
+         *
+         * Ensure that regardless of the parent transformation,
+         * this buffer is always transformed from native display
+         * orientation to display orientation. For example, in the case
+         * of a camera where the buffer remains in native orientation,
+         * we want the pixels to always be upright.
+         */
+        const auto parentTransform = mSnapshot->transform;
+        tr = tr * inverseOrientation(parentTransform.getOrientation());
+
+        // and finally apply it to the original texture matrix
+        const mat4 texTransform(mat4(static_cast<const float*>(textureMatrix)) * tr);
+        memcpy(textureMatrix, texTransform.asArray(), sizeof(textureMatrix));
+    }
+
+    const Rect win{layerSettings.geometry.boundaries};
+    float bufferWidth = static_cast<float>(mSnapshot->bufferSize.getWidth());
+    float bufferHeight = static_cast<float>(mSnapshot->bufferSize.getHeight());
+
+    // Layers can have a "buffer size" of [0, 0, -1, -1] when no display frame has
+    // been set and there is no parent layer bounds. In that case, the scale is meaningless so
+    // ignore them.
+    if (!mSnapshot->bufferSize.isValid()) {
+        bufferWidth = float(win.right) - float(win.left);
+        bufferHeight = float(win.bottom) - float(win.top);
+    }
+
+    const float scaleHeight = (float(win.bottom) - float(win.top)) / bufferHeight;
+    const float scaleWidth = (float(win.right) - float(win.left)) / bufferWidth;
+    const float translateY = float(win.top) / bufferHeight;
+    const float translateX = float(win.left) / bufferWidth;
+
+    // Flip y-coordinates because GLConsumer expects OpenGL convention.
+    mat4 tr = mat4::translate(vec4(.5f, .5f, 0.f, 1.f)) * mat4::scale(vec4(1.f, -1.f, 1.f, 1.f)) *
+            mat4::translate(vec4(-.5f, -.5f, 0.f, 1.f)) *
+            mat4::translate(vec4(translateX, translateY, 0.f, 1.f)) *
+            mat4::scale(vec4(scaleWidth, scaleHeight, 1.0f, 1.0f));
+
+    layerSettings.source.buffer.useTextureFiltering = useFiltering;
+    layerSettings.source.buffer.textureTransform =
+            mat4(static_cast<const float*>(textureMatrix)) * tr;
+
+    return;
+}
+
+void LayerFE::prepareShadowClientComposition(LayerFE::LayerSettings& caster,
+                                             const Rect& layerStackRect) const {
+    renderengine::ShadowSettings state = mSnapshot->shadowSettings;
+    if (state.length <= 0.f || (state.ambientColor.a <= 0.f && state.spotColor.a <= 0.f)) {
+        return;
+    }
+
+    // Shift the spot light x-position to the middle of the display and then
+    // offset it by casting layer's screen pos.
+    state.lightPos.x =
+            (static_cast<float>(layerStackRect.width()) / 2.f) - mSnapshot->transformedBounds.left;
+    state.lightPos.y -= mSnapshot->transformedBounds.top;
+    caster.shadow = state;
+}
+
+void LayerFE::onLayerDisplayed(ftl::SharedFuture<FenceResult> futureFenceResult) {
+    mCompositionResult.releaseFences.emplace_back(std::move(futureFenceResult));
+}
+
+CompositionResult&& LayerFE::stealCompositionResult() {
+    return std::move(mCompositionResult);
+}
+
+const char* LayerFE::getDebugName() const {
+    return mName.c_str();
+}
+
+const LayerMetadata* LayerFE::getMetadata() const {
+    return &mSnapshot->layerMetadata;
+}
+
+const LayerMetadata* LayerFE::getRelativeMetadata() const {
+    return &mSnapshot->relativeLayerMetadata;
+}
+
+int32_t LayerFE::getSequence() const {
+    return mSnapshot->sequence;
+}
+
+bool LayerFE::hasRoundedCorners() const {
+    return mSnapshot->roundedCorner.hasRoundedCorners();
+}
+
+void LayerFE::setWasClientComposed(const sp<Fence>& fence) {
+    mCompositionResult.lastClientCompositionFence = fence;
+}
+
+bool LayerFE::hasBufferOrSidebandStream() const {
+    return mSnapshot->externalTexture || mSnapshot->sidebandStream;
+}
+
+bool LayerFE::fillsColor() const {
+    return mSnapshot->color.r >= 0.0_hf && mSnapshot->color.g >= 0.0_hf &&
+            mSnapshot->color.b >= 0.0_hf;
+}
+
+bool LayerFE::hasBlur() const {
+    return mSnapshot->backgroundBlurRadius > 0 || mSnapshot->blurRegions.size() > 0;
+}
+
+bool LayerFE::drawShadows() const {
+    return mSnapshot->shadowSettings.length > 0.f &&
+            (mSnapshot->shadowSettings.ambientColor.a > 0 ||
+             mSnapshot->shadowSettings.spotColor.a > 0);
+};
+
+const sp<GraphicBuffer> LayerFE::getBuffer() const {
+    return mSnapshot->externalTexture ? mSnapshot->externalTexture->getBuffer() : nullptr;
+}
+
+} // namespace android