refactored screenshot code

the core screenshot function now can capture the screen at any lower resolution
performing bilinear filtering.

we also now have some client code to interface with the screenshot service.

it's now possible to request a screenshot at a lower resolution.

Change-Id: I5a3b0e431421800e3aad601d9af8f94adffbc71f

2 files changed, 58 insertions, 2 deletions

diff --git a/libs/surfaceflinger_client/ISurfaceComposer.cpp b/libs/surfaceflinger_client/ISurfaceComposer.cpp
index 040060e..d676f5e 100644
--- a/libs/surfaceflinger_client/ISurfaceComposer.cpp
+++ b/libs/surfaceflinger_client/ISurfaceComposer.cpp
@@ -126,11 +126,14 @@ public:
 
     virtual status_t captureScreen(DisplayID dpy,
             sp<IMemoryHeap>* heap,
-            uint32_t* width, uint32_t* height, PixelFormat* format)
+            uint32_t* width, uint32_t* height, PixelFormat* format,
+            uint32_t reqWidth, uint32_t reqHeight)
     {
         Parcel data, reply;
         data.writeInterfaceToken(ISurfaceComposer::getInterfaceDescriptor());
         data.writeInt32(dpy);
+        data.writeInt32(reqWidth);
+        data.writeInt32(reqHeight);
         remote()->transact(BnSurfaceComposer::CAPTURE_SCREEN, data, &reply);
         *heap = interface_cast<IMemoryHeap>(reply.readStrongBinder());
         *width = reply.readInt32();
@@ -208,10 +211,13 @@ status_t BnSurfaceComposer::onTransact(
         case CAPTURE_SCREEN: {
             CHECK_INTERFACE(ISurfaceComposer, data, reply);
             DisplayID dpy = data.readInt32();
+            uint32_t reqWidth = data.readInt32();
+            uint32_t reqHeight = data.readInt32();
             sp<IMemoryHeap> heap;
             uint32_t w, h;
             PixelFormat f;
-            status_t res = captureScreen(dpy, &heap, &w, &h, &f);
+            status_t res = captureScreen(dpy, &heap, &w, &h, &f,
+                    reqWidth, reqHeight);
             reply->writeStrongBinder(heap->asBinder());
             reply->writeInt32(w);
             reply->writeInt32(h);
diff --git a/libs/surfaceflinger_client/SurfaceComposerClient.cpp b/libs/surfaceflinger_client/SurfaceComposerClient.cpp
index 4096ac6..f270461 100644
--- a/libs/surfaceflinger_client/SurfaceComposerClient.cpp
+++ b/libs/surfaceflinger_client/SurfaceComposerClient.cpp
@@ -545,5 +545,55 @@ status_t SurfaceComposerClient::setFreezeTint(SurfaceID id, uint32_t tint)
 }
 
 // ----------------------------------------------------------------------------
+
+ScreenshotClient::ScreenshotClient()
+    : mWidth(0), mHeight(0), mFormat(PIXEL_FORMAT_NONE) {
+}
+
+status_t ScreenshotClient::update() {
+    sp<ISurfaceComposer> s(ComposerService::getComposerService());
+    if (s == NULL) return NO_INIT;
+    mHeap = 0;
+    return s->captureScreen(0, &mHeap,
+            &mWidth, &mHeight, &mFormat, 0, 0);
+}
+
+status_t ScreenshotClient::update(uint32_t reqWidth, uint32_t reqHeight) {
+    sp<ISurfaceComposer> s(ComposerService::getComposerService());
+    if (s == NULL) return NO_INIT;
+    mHeap = 0;
+    return s->captureScreen(0, &mHeap,
+            &mWidth, &mHeight, &mFormat, reqWidth, reqHeight);
+}
+
+void ScreenshotClient::release() {
+    mHeap = 0;
+}
+
+void const* ScreenshotClient::getPixels() const {
+    return mHeap->getBase();
+}
+
+uint32_t ScreenshotClient::getWidth() const {
+    return mWidth;
+}
+
+uint32_t ScreenshotClient::getHeight() const {
+    return mHeight;
+}
+
+PixelFormat ScreenshotClient::getFormat() const {
+    return mFormat;
+}
+
+uint32_t ScreenshotClient::getStride() const {
+    return mWidth;
+}
+
+size_t ScreenshotClient::getSize() const {
+    return mHeap->getSize();
+}
+
+// ----------------------------------------------------------------------------
 }; // namespace android