Romain Guy | 4054360 | 2013-06-12 15:31:28 -0700 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright (C) 2013 The Android Open Source Project |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | |
| 17 | #ifndef ANDROID_HWUI_FENCE_H |
| 18 | #define ANDROID_HWUI_FENCE_H |
| 19 | |
| 20 | #include <EGL/egl.h> |
| 21 | #include <EGL/eglext.h> |
| 22 | |
| 23 | namespace android { |
| 24 | namespace uirenderer { |
| 25 | |
| 26 | /** |
| 27 | * Creating a Fence instance inserts a new sync fence in the OpenGL |
| 28 | * commands stream. The caller can then wait for the fence to be signaled |
| 29 | * by calling the wait method. |
| 30 | */ |
| 31 | class Fence { |
| 32 | public: |
| 33 | enum { |
| 34 | /** |
| 35 | * Default timeout in nano-seconds for wait() |
| 36 | */ |
| 37 | kDefaultTimeout = 1000000000 |
| 38 | }; |
| 39 | |
| 40 | /** |
| 41 | * Inserts a new sync fence in the OpenGL commands stream. |
| 42 | */ |
| 43 | Fence() { |
| 44 | mDisplay = eglGetDisplay(EGL_DEFAULT_DISPLAY); |
| 45 | if (mDisplay != EGL_NO_DISPLAY) { |
| 46 | mFence = eglCreateSyncKHR(mDisplay, EGL_SYNC_FENCE_KHR, NULL); |
| 47 | } else { |
| 48 | mFence = EGL_NO_SYNC_KHR; |
| 49 | } |
| 50 | } |
| 51 | |
| 52 | /** |
| 53 | * Destroys the fence. Any caller waiting on the fence will be |
| 54 | * signaled immediately. |
| 55 | */ |
| 56 | ~Fence() { |
| 57 | if (mFence != EGL_NO_SYNC_KHR) { |
| 58 | eglDestroySyncKHR(mDisplay, mFence); |
| 59 | } |
| 60 | } |
| 61 | |
| 62 | /** |
| 63 | * Blocks the calling thread until this fence is signaled, or until |
| 64 | * <timeout> nanoseconds have passed. |
| 65 | * |
| 66 | * Returns true if waiting for the fence was successful, false if |
| 67 | * a timeout or an error occurred. |
| 68 | */ |
| 69 | bool wait(EGLTimeKHR timeout = kDefaultTimeout) { |
| 70 | EGLint waitStatus = eglClientWaitSyncKHR(mDisplay, mFence, |
| 71 | EGL_SYNC_FLUSH_COMMANDS_BIT_KHR, timeout); |
| 72 | if (waitStatus == EGL_FALSE) { |
| 73 | ALOGW("Failed to wait for the fence %#x", eglGetError()); |
| 74 | } |
| 75 | return waitStatus == EGL_CONDITION_SATISFIED_KHR; |
| 76 | } |
| 77 | |
| 78 | private: |
| 79 | EGLDisplay mDisplay; |
| 80 | EGLSyncKHR mFence; |
| 81 | |
| 82 | }; // class Fence |
| 83 | |
| 84 | /** |
| 85 | * An AutoFence creates a Fence instance and waits for the fence |
| 86 | * to be signaled when the AutoFence is destroyed. This is useful |
| 87 | * to automatically wait for a series of OpenGL commands to be |
| 88 | * executed. For example: |
| 89 | * |
| 90 | * void drawAndWait() { |
| 91 | * glDrawElements(); |
| 92 | * AutoFence fence; |
| 93 | * } |
| 94 | */ |
| 95 | class AutoFence { |
| 96 | public: |
| 97 | AutoFence(EGLTimeKHR timeout = Fence::kDefaultTimeout): mTimeout(timeout) { |
| 98 | } |
| 99 | |
| 100 | ~AutoFence() { |
| 101 | mFence.wait(mTimeout); |
| 102 | } |
| 103 | |
| 104 | private: |
| 105 | EGLTimeKHR mTimeout; |
| 106 | Fence mFence; |
| 107 | |
| 108 | }; // class AutoFence |
| 109 | |
| 110 | }; // namespace uirenderer |
| 111 | }; // namespace android |
| 112 | |
| 113 | #endif // ANDROID_HWUI_FENCE_H |