Add a LayerScreenshot

A LayerScreenshot is a special type of layer that contains a screenshot of
the screen acquired when its created. It works just like LayerDim.

Make sure to call compositionComplete() after rendering into a FBO.

Bug: 5446982, 5467587, 5466259
Change-Id: I5d8a1b4c327f9973d950cd4f4c0bca7f62825cd4

6 files changed, 226 insertions, 28 deletions

diff --git a/services/surfaceflinger/Android.mk b/services/surfaceflinger/Android.mk
index dab0705..61a8358 100644
--- a/services/surfaceflinger/Android.mk
+++ b/services/surfaceflinger/Android.mk
@@ -5,6 +5,7 @@ LOCAL_SRC_FILES:= \
     Layer.cpp 								\
     LayerBase.cpp 							\
     LayerDim.cpp 							\
+    LayerScreenshot.cpp						\
     DdmConnection.cpp						\
     DisplayHardware/DisplayHardware.cpp 	\
     DisplayHardware/DisplayHardwareBase.cpp \
diff --git a/services/surfaceflinger/Layer.cpp b/services/surfaceflinger/Layer.cpp
index 34a0d73..f885fc7 100644
--- a/services/surfaceflinger/Layer.cpp
+++ b/services/surfaceflinger/Layer.cpp
@@ -88,16 +88,8 @@ void Layer::onFirstRef()
 
 Layer::~Layer()
 {
-    class MessageDestroyGLState : public MessageBase {
-        GLuint texture;
-    public:
-        MessageDestroyGLState(GLuint texture) : texture(texture) { }
-        virtual bool handler() {
-            glDeleteTextures(1, &texture);
-            return true;
-        }
-    };
-    mFlinger->postMessageAsync( new MessageDestroyGLState(mTextureName) );
+    mFlinger->postMessageAsync(
+            new SurfaceFlinger::MessageDestroyGLTexture(mTextureName) );
 }
 
 void Layer::onFrameQueued() {
diff --git a/services/surfaceflinger/LayerScreenshot.cpp b/services/surfaceflinger/LayerScreenshot.cpp
new file mode 100644
index 0000000..e30ccbf
--- /dev/null
+++ b/services/surfaceflinger/LayerScreenshot.cpp
@@ -0,0 +1,114 @@
+/*
+ * Copyright (C) 2011 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 <stdlib.h>
+#include <stdint.h>
+#include <sys/types.h>
+
+#include <utils/Errors.h>
+#include <utils/Log.h>
+
+#include <ui/GraphicBuffer.h>
+
+#include "LayerScreenshot.h"
+#include "SurfaceFlinger.h"
+#include "DisplayHardware/DisplayHardware.h"
+
+namespace android {
+// ---------------------------------------------------------------------------
+
+LayerScreenshot::LayerScreenshot(SurfaceFlinger* flinger, DisplayID display,
+        const sp<Client>& client)
+    : LayerBaseClient(flinger, display, client),
+      mTextureName(0), mFlinger(flinger)
+{
+}
+
+LayerScreenshot::~LayerScreenshot()
+{
+    if (mTextureName) {
+        mFlinger->postMessageAsync(
+                new SurfaceFlinger::MessageDestroyGLTexture(mTextureName) );
+    }
+}
+
+status_t LayerScreenshot::capture() {
+    GLfloat u, v;
+    status_t result = mFlinger->renderScreenToTexture(0, &mTextureName, &u, &v);
+    if (result != NO_ERROR) {
+        return result;
+    }
+
+    glBindTexture(GL_TEXTURE_2D, mTextureName);
+    glTexParameterx(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+    glTexParameterx(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+
+    mTexCoords[0] = 0;         mTexCoords[1] = v;
+    mTexCoords[2] = 0;         mTexCoords[3] = 0;
+    mTexCoords[4] = u;         mTexCoords[5] = 0;
+    mTexCoords[6] = u;         mTexCoords[7] = v;
+
+    return NO_ERROR;
+}
+
+void LayerScreenshot::onDraw(const Region& clip) const
+{
+    const State& s(drawingState());
+    Region::const_iterator it = clip.begin();
+    Region::const_iterator const end = clip.end();
+    if (s.alpha>0 && (it != end)) {
+        const DisplayHardware& hw(graphicPlane(0).displayHardware());
+        const GLfloat alpha = s.alpha/255.0f;
+        const uint32_t fbHeight = hw.getHeight();
+
+        if (s.alpha == 0xFF) {
+            glDisable(GL_BLEND);
+        } else {
+            glEnable(GL_BLEND);
+            glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+        }
+
+        glColor4f(0, 0, 0, alpha);
+
+        glDisable(GL_TEXTURE_EXTERNAL_OES);
+        glEnable(GL_TEXTURE_2D);
+
+        glBindTexture(GL_TEXTURE_2D, mTextureName);
+        glTexEnvx(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
+        glMatrixMode(GL_TEXTURE);
+        glLoadIdentity();
+        glMatrixMode(GL_MODELVIEW);
+
+        glEnableClientState(GL_TEXTURE_COORD_ARRAY);
+        glTexCoordPointer(2, GL_FLOAT, 0, mTexCoords);
+        glVertexPointer(2, GL_FLOAT, 0, mVertices);
+
+        while (it != end) {
+            const Rect& r = *it++;
+            const GLint sy = fbHeight - (r.top + r.height());
+            glScissor(r.left, sy, r.width(), r.height());
+            glDrawArrays(GL_TRIANGLE_FAN, 0, 4);
+        }
+
+        glDisable(GL_BLEND);
+        glDisable(GL_TEXTURE_2D);
+        glDisableClientState(GL_TEXTURE_COORD_ARRAY);
+    }
+}
+
+// ---------------------------------------------------------------------------
+
+}; // namespace android
diff --git a/services/surfaceflinger/LayerScreenshot.h b/services/surfaceflinger/LayerScreenshot.h
new file mode 100644
index 0000000..e3a2b19
--- /dev/null
+++ b/services/surfaceflinger/LayerScreenshot.h
@@ -0,0 +1,56 @@
+/*
+ * Copyright (C) 2011 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.
+ */
+
+#ifndef ANDROID_LAYER_SCREENSHOT_H
+#define ANDROID_LAYER_SCREENSHOT_H
+
+#include <stdint.h>
+#include <sys/types.h>
+
+#include <EGL/egl.h>
+#include <EGL/eglext.h>
+
+#include "LayerBase.h"
+
+// ---------------------------------------------------------------------------
+
+namespace android {
+
+class LayerScreenshot : public LayerBaseClient
+{
+    GLuint mTextureName;
+    GLfloat mTexCoords[8];
+    sp<SurfaceFlinger> mFlinger;
+public:    
+            LayerScreenshot(SurfaceFlinger* flinger, DisplayID display,
+                        const sp<Client>& client);
+        virtual ~LayerScreenshot();
+
+        status_t capture();
+
+    virtual void onDraw(const Region& clip) const;
+    virtual bool isOpaque() const         { return false; }
+    virtual bool isSecure() const         { return false; }
+    virtual bool isProtectedByApp() const { return false; }
+    virtual bool isProtectedByDRM() const { return false; }
+    virtual const char* getTypeId() const { return "LayerScreenshot"; }
+};
+
+// ---------------------------------------------------------------------------
+
+}; // namespace android
+
+#endif // ANDROID_LAYER_SCREENSHOT_H
diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index 595ec1e..ad1995d 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -50,6 +50,7 @@
 #include "DdmConnection.h"
 #include "Layer.h"
 #include "LayerDim.h"
+#include "LayerScreenshot.h"
 #include "SurfaceFlinger.h"
 
 #include "DisplayHardware/DisplayHardware.h"
@@ -1358,6 +1359,9 @@ sp<ISurface> SurfaceFlinger::createSurface(
         case eFXSurfaceDim:
             layer = createDimSurface(client, d, w, h, flags);
             break;
+        case eFXSurfaceScreenshot:
+            layer = createScreenshotSurface(client, d, w, h, flags);
+            break;
     }
 
     if (layer != 0) {
@@ -1420,7 +1424,19 @@ sp<LayerDim> SurfaceFlinger::createDimSurface(
         uint32_t w, uint32_t h, uint32_t flags)
 {
     sp<LayerDim> layer = new LayerDim(this, display, client);
-    layer->initStates(w, h, flags);
+    return layer;
+}
+
+sp<LayerScreenshot> SurfaceFlinger::createScreenshotSurface(
+        const sp<Client>& client, DisplayID display,
+        uint32_t w, uint32_t h, uint32_t flags)
+{
+    sp<LayerScreenshot> layer = new LayerScreenshot(this, display, client);
+    status_t err = layer->capture();
+    if (err != NO_ERROR) {
+        layer.clear();
+        LOGW("createScreenshotSurface failed (%s)", strerror(-err));
+    }
     return layer;
 }
 
@@ -1783,6 +1799,13 @@ void SurfaceFlinger::repaintEverything() {
 
 // ---------------------------------------------------------------------------
 
+status_t SurfaceFlinger::renderScreenToTexture(DisplayID dpy,
+        GLuint* textureName, GLfloat* uOut, GLfloat* vOut)
+{
+    Mutex::Autolock _l(mStateLock);
+    return renderScreenToTextureLocked(dpy, textureName, uOut, vOut);
+}
+
 status_t SurfaceFlinger::renderScreenToTextureLocked(DisplayID dpy,
         GLuint* textureName, GLfloat* uOut, GLfloat* vOut)
 {
@@ -1833,6 +1856,8 @@ status_t SurfaceFlinger::renderScreenToTextureLocked(DisplayID dpy,
         layer->drawForSreenShot();
     }
 
+    hw.compositionComplete();
+
     // back to main framebuffer
     glBindFramebufferOES(GL_FRAMEBUFFER_OES, 0);
     glDisable(GL_SCISSOR_TEST);
@@ -1848,11 +1873,6 @@ status_t SurfaceFlinger::renderScreenToTextureLocked(DisplayID dpy,
 
 status_t SurfaceFlinger::electronBeamOffAnimationImplLocked()
 {
-    status_t result = PERMISSION_DENIED;
-
-    if (!GLExtensions::getInstance().haveFramebufferObject())
-        return INVALID_OPERATION;
-
     // get screen geometry
     const DisplayHardware& hw(graphicPlane(0).displayHardware());
     const uint32_t hw_w = hw.getWidth();
@@ -1861,7 +1881,7 @@ status_t SurfaceFlinger::electronBeamOffAnimationImplLocked()
 
     GLfloat u, v;
     GLuint tname;
-    result = renderScreenToTextureLocked(0, &tname, &u, &v);
+    status_t result = renderScreenToTextureLocked(0, &tname, &u, &v);
     if (result != NO_ERROR) {
         return result;
     }
@@ -2038,10 +2058,6 @@ status_t SurfaceFlinger::electronBeamOnAnimationImplLocked()
         return result;
     }
 
-    // back to main framebuffer
-    glBindFramebufferOES(GL_FRAMEBUFFER_OES, 0);
-    glDisable(GL_SCISSOR_TEST);
-
     GLfloat vtx[8];
     const GLfloat texCoords[4][2] = { {0,v}, {0,0}, {u,0}, {u,v} };
     glBindTexture(GL_TEXTURE_2D, tname);
diff --git a/services/surfaceflinger/SurfaceFlinger.h b/services/surfaceflinger/SurfaceFlinger.h
index 0e642c1..3c8f4e5 100644
--- a/services/surfaceflinger/SurfaceFlinger.h
+++ b/services/surfaceflinger/SurfaceFlinger.h
@@ -49,6 +49,7 @@ class DisplayHardware;
 class FreezeLock;
 class Layer;
 class LayerDim;
+class LayerScreenshot;
 struct surface_flinger_cblk_t;
 
 #define LIKELY( exp )       (__builtin_expect( (exp) != 0, true  ))
@@ -186,6 +187,15 @@ public:
             void                        screenReleased(DisplayID dpy);
             void                        screenAcquired(DisplayID dpy);
 
+            status_t renderScreenToTexture(DisplayID dpy,
+                    GLuint* textureName, GLfloat* uOut, GLfloat* vOut);
+
+            status_t postMessageAsync(const sp<MessageBase>& msg,
+                    nsecs_t reltime=0, uint32_t flags = 0);
+
+            status_t postMessageSync(const sp<MessageBase>& msg,
+                    nsecs_t reltime=0, uint32_t flags = 0);
+
     status_t removeLayer(const sp<LayerBase>& layer);
     status_t addLayer(const sp<LayerBase>& layer);
     status_t invalidateLayerVisibility(const sp<LayerBase>& layer);
@@ -195,6 +205,18 @@ public:
 
     GLuint getProtectedTexName() const { return mProtectedTexName; }
 
+
+    class MessageDestroyGLTexture : public MessageBase {
+        GLuint texture;
+    public:
+        MessageDestroyGLTexture(GLuint texture) : texture(texture) { }
+        virtual bool handler() {
+            glDeleteTextures(1, &texture);
+            return true;
+        }
+    };
+
+
 private:
     // DeathRecipient interface
     virtual void binderDied(const wp<IBinder>& who);
@@ -204,7 +226,6 @@ private:
     friend class LayerBase;
     friend class LayerBaseClient;
     friend class Layer;
-    friend class LayerDim;
 
     sp<ISurface> createSurface(
             ISurfaceComposerClient::surface_data_t* params,
@@ -222,6 +243,10 @@ private:
             const sp<Client>& client, DisplayID display,
             uint32_t w, uint32_t h, uint32_t flags);
 
+    sp<LayerScreenshot> createScreenshotSurface(
+            const sp<Client>& client, DisplayID display,
+            uint32_t w, uint32_t h, uint32_t flags);
+
     status_t removeSurface(const sp<Client>& client, SurfaceID sid);
     status_t destroySurface(const wp<LayerBaseClient>& layer);
     uint32_t setClientStateLocked(const sp<Client>& client, const layer_state_t& s);
@@ -329,12 +354,6 @@ private:
 
     mutable     MessageQueue    mEventQueue;
 
-    status_t postMessageAsync(const sp<MessageBase>& msg,
-            nsecs_t reltime=0, uint32_t flags = 0);
-
-    status_t postMessageSync(const sp<MessageBase>& msg,
-            nsecs_t reltime=0, uint32_t flags = 0);
-
                 // access must be protected by mStateLock
     mutable     Mutex                   mStateLock;
                 State                   mCurrentState;