commit 69e5adffb19135d51bde8e458f4907d7265f3e23
author Chris Craik <ccraik@google.com> Thu Aug 14 13:34:01 2014 -0700
committer Chris Craik <ccraik@google.com> Fri Aug 15 00:59:44 2014 +0000
tree 022fc23512ae5adfbe3f86351305bc9f4538a68a
parent e222e359a0aab985488a711f6edb76820fe8c6df

Define shadow casting behavior within layers

bug:15860114

Savelayers and HW layers both now support shadow casting.

For save layers, the light source should always be correct, for HW
layers, the light source position is set when the layer is created,
and updated when it is resized.

Change-Id: Ie85567dd43c2bb0a0b08fd0bd4db41efa793ac2b

libs/hwui/Layer.cpp

diff --git a/libs/hwui/Layer.cpp b/libs/hwui/Layer.cpp
index d05cabc..8639ae1 100644
--- a/libs/hwui/Layer.cpp
+++ b/libs/hwui/Layer.cpp
@@ -53,6 +53,7 @@
     deferredList = NULL;
     convexMask = NULL;
     caches.resourceCache.incrementRefcount(this);
+    rendererLightPosDirty = true;
 }
 
 Layer::~Layer() {
@@ -80,6 +81,17 @@
     }
 }
 
+void Layer::updateLightPosFromRenderer(const OpenGLRenderer& rootRenderer) {
+    if (renderer && rendererLightPosDirty) {
+        // re-init renderer's light position, based upon last cached location in window
+        Vector3 lightPos = rootRenderer.getLightCenter();
+        cachedInvTransformInWindow.mapPoint3d(lightPos);
+        renderer->initLight(lightPos, rootRenderer.getLightRadius(),
+                rootRenderer.getAmbientShadowAlpha(), rootRenderer.getSpotShadowAlpha());
+        rendererLightPosDirty = false;
+    }
+}
+
 bool Layer::resize(const uint32_t width, const uint32_t height) {
     uint32_t desiredWidth = computeIdealWidth(width);
     uint32_t desiredHeight = computeIdealWidth(height);
@@ -203,7 +215,8 @@
     }
 }
 
-void Layer::defer() {
+void Layer::defer(const OpenGLRenderer& rootRenderer) {
+    updateLightPosFromRenderer(rootRenderer);
     const float width = layer.getWidth();
     const float height = layer.getHeight();
 
@@ -253,7 +266,8 @@
     }
 }
 
-void Layer::render() {
+void Layer::render(const OpenGLRenderer& rootRenderer) {
+    updateLightPosFromRenderer(rootRenderer);
     renderer->setViewport(layer.getWidth(), layer.getHeight());
     renderer->prepareDirty(dirtyRect.left, dirtyRect.top, dirtyRect.right, dirtyRect.bottom,
             !isBlend());