commit 5a50ac8819525f851c677be88a466b14737dbb18
author bohu <bohu@google.com> Mon Jan 26 09:25:23 2015 -0800
committer bohu <bohu@google.com> Mon Jan 26 11:26:25 2015 -0800
tree 7a377f350404b364e961b49cc85b54bb57d72a17
parent 7d9f6e9b35c43e19b810a089557e561f5f2b63bf

guest system gles fix: Enable screen capture with gpu on

Currently, when running emulator with gpu on, screen capture does not work.
This commit fixes that by doing the following steps:
1. enable gralloc to allocate buffer in gralloc_alloc for screen capture
   usage mode.
2. read back screen pixels in gralloc_lock for screen capture usage mode

Note: This commit only fixes guest side, and to make screen capture work,
we also need the corresponding fix on host side in the following CL:
    e36c098b5563adcc7442cb3a172ff769ee3fb4b6

Change-Id: I24b91bb70669fe2ddad3a5fc2eaccf3f3eaa0e1b

opengl/system/gralloc/gralloc.cpp

diff --git a/opengl/system/gralloc/gralloc.cpp b/opengl/system/gralloc/gralloc.cpp
index a6f7d91..d74af08 100644
--- a/opengl/system/gralloc/gralloc.cpp
+++ b/opengl/system/gralloc/gralloc.cpp
@@ -141,9 +141,11 @@
     bool sw_write = (0 != (usage & GRALLOC_USAGE_SW_WRITE_MASK));
     bool hw_write = (usage & GRALLOC_USAGE_HW_RENDER);
     if (hw_write && sw_write) {
-        ALOGE("gralloc_alloc: Mismatched usage flags: %d x %d, usage %x",
-                w, h, usage);
-        return -EINVAL;
+        // screen-capture has both hw_write and sw_write enabled, and we
+        // should allow this usage.
+        // ALOGE("gralloc_alloc: Mismatched usage flags: %d x %d, usage %x",
+        //         w, h, usage);
+        // return -EINVAL;
     }
     bool sw_read = (0 != (usage & GRALLOC_USAGE_SW_READ_MASK));
     bool hw_cam_write = usage & GRALLOC_USAGE_HW_CAMERA_WRITE;
@@ -685,6 +687,15 @@
             return -EBUSY;
         }
 
+        const bool sw_read = (cb->usage & GRALLOC_USAGE_SW_READ_MASK);
+        const bool hw_write = (cb->usage & GRALLOC_USAGE_HW_RENDER);
+        const bool screen_capture_mode = (sw_read && hw_write);
+        if (screen_capture_mode) {
+            D("gralloc_lock read back color buffer %d %d\n", cb->width, cb->height);
+            DEFINE_AND_VALIDATE_HOST_CONNECTION;
+            rcEnc->rcReadColorBuffer(rcEnc, cb->hostHandle,
+                    0, 0, cb->width, cb->height, GL_RGBA, GL_UNSIGNED_BYTE, cpu_addr);
+        }
     }
 
     //