services/jni/com_android_server_AssetAtlasService.cpp

   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 #define LOG_TAG "AssetAtlasService"
  18
  19 #include "jni.h"
  20 #include "JNIHelp.h"
  21
  22 #include <android_view_GraphicBuffer.h>
  23 #include <cutils/log.h>
  24
  25 #include <GLES2/gl2.h>
  26 #include <GLES2/gl2ext.h>
  27
  28 #include <EGL/egl.h>
  29 #include <EGL/eglext.h>
  30
  31 #include <SkCanvas.h>
  32 #include <SkBitmap.h>
  33
  34 namespace android {
  35
  36 // ----------------------------------------------------------------------------
  37 // Defines
  38 // ----------------------------------------------------------------------------
  39
  40 // Defines how long to wait for the GPU when uploading the atlas
  41 // This timeout is defined in nanoseconds (see EGL_KHR_fence_sync extension)
  42 #define FENCE_TIMEOUT 2000000000
  43
  44 // ----------------------------------------------------------------------------
  45 // JNI Helpers
  46 // ----------------------------------------------------------------------------
  47
  48 static struct {
  49     jfieldID mFinalizer;
  50     jfieldID mNativeCanvas;
  51 } gCanvasClassInfo;
  52
  53 static struct {
  54     jfieldID mNativeCanvas;
  55 } gCanvasFinalizerClassInfo;
  56
  57 #define GET_INT(object, field) \
  58     env->GetIntField(object, field)
  59
  60 #define SET_INT(object, field, value) \
  61     env->SetIntField(object, field, value)
  62
  63 // ----------------------------------------------------------------------------
  64 // Canvas management
  65 // ----------------------------------------------------------------------------
  66
  67 static inline void swapCanvasPtr(JNIEnv* env, jobject canvasObj, SkCanvas* newCanvas) {
  68     jobject canvasFinalizerObj = env->GetObjectField(canvasObj, gCanvasClassInfo.mFinalizer);
  69     SkCanvas* previousCanvas = reinterpret_cast<SkCanvas*>(
  70             GET_INT(canvasObj, gCanvasClassInfo.mNativeCanvas));
  71     SET_INT(canvasObj, gCanvasClassInfo.mNativeCanvas, (int) newCanvas);
  72     SET_INT(canvasFinalizerObj, gCanvasFinalizerClassInfo.mNativeCanvas, (int) newCanvas);
  73     SkSafeUnref(previousCanvas);
  74 }
  75
  76 static SkBitmap* com_android_server_AssetAtlasService_acquireCanvas(JNIEnv* env, jobject,
  77         jobject canvas, jint width, jint height) {
  78
  79     SkBitmap* bitmap = new SkBitmap;
  80     bitmap->setConfig(SkBitmap::kARGB_8888_Config, width, height);
  81     bitmap->allocPixels();
  82     bitmap->eraseColor(0);
  83
  84     SkCanvas* nativeCanvas = SkNEW_ARGS(SkCanvas, (*bitmap));
  85     swapCanvasPtr(env, canvas, nativeCanvas);
  86
  87     return bitmap;
  88 }
  89
  90 static void com_android_server_AssetAtlasService_releaseCanvas(JNIEnv* env, jobject,
  91         jobject canvas, SkBitmap* bitmap) {
  92
  93     SkCanvas* nativeCanvas = SkNEW(SkCanvas);
  94     swapCanvasPtr(env, canvas, nativeCanvas);
  95
  96     delete bitmap;
  97 }
  98
  99 #define CLEANUP_GL_AND_RETURN(result) \
 100     if (fence != EGL_NO_SYNC_KHR) eglDestroySyncKHR(display, fence); \
 101     if (image) eglDestroyImageKHR(display, image); \
 102     if (texture) glDeleteTextures(1, &texture); \
 103     if (surface != EGL_NO_SURFACE) eglDestroySurface(display, surface); \
 104     if (context != EGL_NO_CONTEXT) eglDestroyContext(display, context); \
 105     eglMakeCurrent(display, EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT); \
 106     eglReleaseThread(); \
 107     eglTerminate(display); \
 108     return result;
 109
 110 static jboolean com_android_server_AssetAtlasService_upload(JNIEnv* env, jobject,
 111         jobject graphicBuffer, SkBitmap* bitmap) {
 112
 113     // The goal of this method is to copy the bitmap into the GraphicBuffer
 114     // using the GPU to swizzle the texture content
 115     sp<GraphicBuffer> buffer(graphicBufferForJavaObject(env, graphicBuffer));
 116
 117     if (buffer != NULL) {
 118         EGLDisplay display = eglGetDisplay(EGL_DEFAULT_DISPLAY);
 119         if (display == EGL_NO_DISPLAY) return false;
 120
 121         EGLint major;
 122         EGLint minor;
 123         if (!eglInitialize(display, &major, &minor)) {
 124             ALOGW("Could not initialize EGL");
 125             return false;
 126         }
 127
 128         // We're going to use a 1x1 pbuffer surface later on
 129         // The configuration doesn't really matter for what we're trying to do
 130         EGLint configAttrs[] = {
 131                 EGL_RENDERABLE_TYPE, EGL_OPENGL_ES2_BIT,
 132                 EGL_RED_SIZE, 8,
 133                 EGL_GREEN_SIZE, 8,
 134                 EGL_BLUE_SIZE, 8,
 135                 EGL_ALPHA_SIZE, 0,
 136                 EGL_DEPTH_SIZE, 0,
 137                 EGL_STENCIL_SIZE, 0,
 138                 EGL_NONE
 139         };
 140         EGLConfig configs[1];
 141         EGLint configCount;
 142         if (!eglChooseConfig(display, configAttrs, configs, 1, &configCount)) {
 143             ALOGW("Could not select EGL configuration");
 144             eglReleaseThread();
 145             eglTerminate(display);
 146             return false;
 147         }
 148         if (configCount <= 0) {
 149             ALOGW("Could not find EGL configuration");
 150             eglReleaseThread();
 151             eglTerminate(display);
 152             return false;
 153         }
 154
 155         // These objects are initialized below but the default "null"
 156         // values are used to cleanup properly at any point in the
 157         // initialization sequence
 158         GLuint texture = 0;
 159         EGLImageKHR image = EGL_NO_IMAGE_KHR;
 160         EGLSurface surface = EGL_NO_SURFACE;
 161         EGLSyncKHR fence = EGL_NO_SYNC_KHR;
 162
 163         EGLint attrs[] = { EGL_CONTEXT_CLIENT_VERSION, 2, EGL_NONE };
 164         EGLContext context = eglCreateContext(display, configs[0], EGL_NO_CONTEXT, attrs);
 165         if (context == EGL_NO_CONTEXT) {
 166             ALOGW("Could not create EGL context");
 167             CLEANUP_GL_AND_RETURN(false);
 168         }
 169
 170         // Create the 1x1 pbuffer
 171         EGLint surfaceAttrs[] = { EGL_WIDTH, 1, EGL_HEIGHT, 1, EGL_NONE };
 172         surface = eglCreatePbufferSurface(display, configs[0], surfaceAttrs);
 173         if (surface == EGL_NO_SURFACE) {
 174             ALOGW("Could not create EGL surface");
 175             CLEANUP_GL_AND_RETURN(false);
 176         }
 177
 178         if (!eglMakeCurrent(display, surface, surface, context)) {
 179             ALOGW("Could not change current EGL context");
 180             CLEANUP_GL_AND_RETURN(false);
 181         }
 182
 183         // We use an EGLImage to access the content of the GraphicBuffer
 184         // The EGL image is later bound to a 2D texture
 185         EGLClientBuffer clientBuffer = (EGLClientBuffer) buffer->getNativeBuffer();
 186         EGLint imageAttrs[] = { EGL_IMAGE_PRESERVED_KHR, EGL_TRUE, EGL_NONE };
 187         image = eglCreateImageKHR(display, EGL_NO_CONTEXT,
 188                 EGL_NATIVE_BUFFER_ANDROID, clientBuffer, imageAttrs);
 189         if (image == EGL_NO_IMAGE_KHR) {
 190             ALOGW("Could not create EGL image");
 191             CLEANUP_GL_AND_RETURN(false);
 192         }
 193
 194         glGenTextures(1, &texture);
 195         glBindTexture(GL_TEXTURE_2D, texture);
 196         glEGLImageTargetTexture2DOES(GL_TEXTURE_2D, image);
 197         if (glGetError() != GL_NO_ERROR) {
 198             ALOGW("Could not create/bind texture");
 199             CLEANUP_GL_AND_RETURN(false);
 200         }
 201
 202         // Upload the content of the bitmap in the GraphicBuffer
 203         glPixelStorei(GL_UNPACK_ALIGNMENT, bitmap->bytesPerPixel());
 204         glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, bitmap->width(), bitmap->height(),
 205                 GL_RGBA, GL_UNSIGNED_BYTE, bitmap->getPixels());
 206         if (glGetError() != GL_NO_ERROR) {
 207             ALOGW("Could not upload to texture");
 208             CLEANUP_GL_AND_RETURN(false);
 209         }
 210
 211         // The fence is used to wait for the texture upload to finish
 212         // properly. We cannot rely on glFlush() and glFinish() as
 213         // some drivers completely ignore these API calls
 214         fence = eglCreateSyncKHR(display, EGL_SYNC_FENCE_KHR, NULL);
 215         if (fence == EGL_NO_SYNC_KHR) {
 216             ALOGW("Could not create sync fence %#x", eglGetError());
 217             CLEANUP_GL_AND_RETURN(false);
 218         }
 219
 220         // The flag EGL_SYNC_FLUSH_COMMANDS_BIT_KHR will trigger a
 221         // pipeline flush (similar to what a glFlush() would do.)
 222         EGLint waitStatus = eglClientWaitSyncKHR(display, fence,
 223                 EGL_SYNC_FLUSH_COMMANDS_BIT_KHR, FENCE_TIMEOUT);
 224         if (waitStatus != EGL_CONDITION_SATISFIED_KHR) {
 225             ALOGW("Failed to wait for the fence %#x", eglGetError());
 226             CLEANUP_GL_AND_RETURN(false);
 227         }
 228
 229         CLEANUP_GL_AND_RETURN(true);
 230     }
 231
 232     return false;
 233 }
 234
 235 // ----------------------------------------------------------------------------
 236 // JNI Glue
 237 // ----------------------------------------------------------------------------
 238
 239 #define FIND_CLASS(var, className) \
 240         var = env->FindClass(className); \
 241         LOG_FATAL_IF(! var, "Unable to find class " className);
 242
 243 #define GET_FIELD_ID(var, clazz, fieldName, fieldDescriptor) \
 244         var = env->GetFieldID(clazz, fieldName, fieldDescriptor); \
 245         LOG_FATAL_IF(! var, "Unable to find field " fieldName);
 246
 247 const char* const kClassPathName = "com/android/server/AssetAtlasService";
 248
 249 static JNINativeMethod gMethods[] = {
 250     { "nAcquireAtlasCanvas", "(Landroid/graphics/Canvas;II)I",
 251             (void*) com_android_server_AssetAtlasService_acquireCanvas },
 252     { "nReleaseAtlasCanvas", "(Landroid/graphics/Canvas;I)V",
 253             (void*) com_android_server_AssetAtlasService_releaseCanvas },
 254     { "nUploadAtlas", "(Landroid/view/GraphicBuffer;I)Z",
 255             (void*) com_android_server_AssetAtlasService_upload },
 256 };
 257
 258 int register_android_server_AssetAtlasService(JNIEnv* env) {
 259     jclass clazz;
 260
 261     FIND_CLASS(clazz, "android/graphics/Canvas");
 262     GET_FIELD_ID(gCanvasClassInfo.mFinalizer, clazz, "mFinalizer",
 263             "Landroid/graphics/Canvas$CanvasFinalizer;");
 264     GET_FIELD_ID(gCanvasClassInfo.mNativeCanvas, clazz, "mNativeCanvas", "I");
 265
 266     FIND_CLASS(clazz, "android/graphics/Canvas$CanvasFinalizer");
 267     GET_FIELD_ID(gCanvasFinalizerClassInfo.mNativeCanvas, clazz, "mNativeCanvas", "I");
 268
 269     return jniRegisterNativeMethods(env, kClassPathName, gMethods, NELEM(gMethods));
 270 }
 271
 272 };