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      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 #include "android/graphics/GraphicsJNI.h"
     22 
     23 #include <android_view_GraphicBuffer.h>
     24 #include <cutils/log.h>
     25 
     26 #include <GLES2/gl2.h>
     27 #include <GLES2/gl2ext.h>
     28 
     29 #include <EGL/egl.h>
     30 #include <EGL/eglext.h>
     31 
     32 #include <SkCanvas.h>
     33 #include <SkBitmap.h>
     34 
     35 namespace android {
     36 
     37 // ----------------------------------------------------------------------------
     38 // Defines
     39 // ----------------------------------------------------------------------------
     40 
     41 // Defines how long to wait for the GPU when uploading the atlas
     42 // This timeout is defined in nanoseconds (see EGL_KHR_fence_sync extension)
     43 #define FENCE_TIMEOUT 2000000000
     44 
     45 // ----------------------------------------------------------------------------
     46 // JNI Helpers
     47 // ----------------------------------------------------------------------------
     48 
     49 static struct {
     50     jmethodID setNativeBitmap;
     51 } gCanvasClassInfo;
     52 
     53 #define INVOKEV(object, method, ...) \
     54     env->CallVoidMethod(object, method, __VA_ARGS__)
     55 
     56 // ----------------------------------------------------------------------------
     57 // Canvas management
     58 // ----------------------------------------------------------------------------
     59 
     60 static jlong com_android_server_AssetAtlasService_acquireCanvas(JNIEnv* env, jobject,
     61         jobject canvas, jint width, jint height) {
     62 
     63     SkBitmap* bitmap = new SkBitmap;
     64     bitmap->allocN32Pixels(width, height);
     65     bitmap->eraseColor(0);
     66     INVOKEV(canvas, gCanvasClassInfo.setNativeBitmap, reinterpret_cast<jlong>(bitmap));
     67 
     68     return reinterpret_cast<jlong>(bitmap);
     69 }
     70 
     71 static void com_android_server_AssetAtlasService_releaseCanvas(JNIEnv* env, jobject,
     72         jobject canvas, jlong bitmapHandle) {
     73 
     74     SkBitmap* bitmap = reinterpret_cast<SkBitmap*>(bitmapHandle);
     75     INVOKEV(canvas, gCanvasClassInfo.setNativeBitmap, (jlong)0);
     76 
     77     delete bitmap;
     78 }
     79 
     80 #define CLEANUP_GL_AND_RETURN(result) \
     81     if (fence != EGL_NO_SYNC_KHR) eglDestroySyncKHR(display, fence); \
     82     if (image) eglDestroyImageKHR(display, image); \
     83     if (texture) glDeleteTextures(1, &texture); \
     84     if (surface != EGL_NO_SURFACE) eglDestroySurface(display, surface); \
     85     if (context != EGL_NO_CONTEXT) eglDestroyContext(display, context); \
     86     eglMakeCurrent(display, EGL_NO_SURFACE, EGL_NO_SURFACE, EGL_NO_CONTEXT); \
     87     eglReleaseThread(); \
     88     eglTerminate(display); \
     89     return result;
     90 
     91 static jboolean com_android_server_AssetAtlasService_upload(JNIEnv* env, jobject,
     92         jobject graphicBuffer, jlong bitmapHandle) {
     93 
     94     SkBitmap* bitmap = reinterpret_cast<SkBitmap*>(bitmapHandle);
     95     // The goal of this method is to copy the bitmap into the GraphicBuffer
     96     // using the GPU to swizzle the texture content
     97     sp<GraphicBuffer> buffer(graphicBufferForJavaObject(env, graphicBuffer));
     98 
     99     if (buffer != NULL) {
    100         EGLDisplay display = eglGetDisplay(EGL_DEFAULT_DISPLAY);
    101         if (display == EGL_NO_DISPLAY) return JNI_FALSE;
    102 
    103         EGLint major;
    104         EGLint minor;
    105         if (!eglInitialize(display, &major, &minor)) {
    106             ALOGW("Could not initialize EGL");
    107             return JNI_FALSE;
    108         }
    109 
    110         // We're going to use a 1x1 pbuffer surface later on
    111         // The configuration doesn't really matter for what we're trying to do
    112         EGLint configAttrs[] = {
    113                 EGL_RENDERABLE_TYPE, EGL_OPENGL_ES2_BIT,
    114                 EGL_RED_SIZE, 8,
    115                 EGL_GREEN_SIZE, 8,
    116                 EGL_BLUE_SIZE, 8,
    117                 EGL_ALPHA_SIZE, 0,
    118                 EGL_DEPTH_SIZE, 0,
    119                 EGL_STENCIL_SIZE, 0,
    120                 EGL_NONE
    121         };
    122         EGLConfig configs[1];
    123         EGLint configCount;
    124         if (!eglChooseConfig(display, configAttrs, configs, 1, &configCount)) {
    125             ALOGW("Could not select EGL configuration");
    126             eglReleaseThread();
    127             eglTerminate(display);
    128             return JNI_FALSE;
    129         }
    130         if (configCount <= 0) {
    131             ALOGW("Could not find EGL configuration");
    132             eglReleaseThread();
    133             eglTerminate(display);
    134             return JNI_FALSE;
    135         }
    136 
    137         // These objects are initialized below but the default "null"
    138         // values are used to cleanup properly at any point in the
    139         // initialization sequence
    140         GLuint texture = 0;
    141         EGLImageKHR image = EGL_NO_IMAGE_KHR;
    142         EGLSurface surface = EGL_NO_SURFACE;
    143         EGLSyncKHR fence = EGL_NO_SYNC_KHR;
    144 
    145         EGLint attrs[] = { EGL_CONTEXT_CLIENT_VERSION, 2, EGL_NONE };
    146         EGLContext context = eglCreateContext(display, configs[0], EGL_NO_CONTEXT, attrs);
    147         if (context == EGL_NO_CONTEXT) {
    148             ALOGW("Could not create EGL context");
    149             CLEANUP_GL_AND_RETURN(JNI_FALSE);
    150         }
    151 
    152         // Create the 1x1 pbuffer
    153         EGLint surfaceAttrs[] = { EGL_WIDTH, 1, EGL_HEIGHT, 1, EGL_NONE };
    154         surface = eglCreatePbufferSurface(display, configs[0], surfaceAttrs);
    155         if (surface == EGL_NO_SURFACE) {
    156             ALOGW("Could not create EGL surface");
    157             CLEANUP_GL_AND_RETURN(JNI_FALSE);
    158         }
    159 
    160         if (!eglMakeCurrent(display, surface, surface, context)) {
    161             ALOGW("Could not change current EGL context");
    162             CLEANUP_GL_AND_RETURN(JNI_FALSE);
    163         }
    164 
    165         // We use an EGLImage to access the content of the GraphicBuffer
    166         // The EGL image is later bound to a 2D texture
    167         EGLClientBuffer clientBuffer = (EGLClientBuffer) buffer->getNativeBuffer();
    168         EGLint imageAttrs[] = { EGL_IMAGE_PRESERVED_KHR, EGL_TRUE, EGL_NONE };
    169         image = eglCreateImageKHR(display, EGL_NO_CONTEXT,
    170                 EGL_NATIVE_BUFFER_ANDROID, clientBuffer, imageAttrs);
    171         if (image == EGL_NO_IMAGE_KHR) {
    172             ALOGW("Could not create EGL image");
    173             CLEANUP_GL_AND_RETURN(JNI_FALSE);
    174         }
    175 
    176         glGenTextures(1, &texture);
    177         glBindTexture(GL_TEXTURE_2D, texture);
    178         glEGLImageTargetTexture2DOES(GL_TEXTURE_2D, image);
    179         if (glGetError() != GL_NO_ERROR) {
    180             ALOGW("Could not create/bind texture");
    181             CLEANUP_GL_AND_RETURN(JNI_FALSE);
    182         }
    183 
    184         // Upload the content of the bitmap in the GraphicBuffer
    185         glPixelStorei(GL_UNPACK_ALIGNMENT, bitmap->bytesPerPixel());
    186         glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, bitmap->width(), bitmap->height(),
    187                 GL_RGBA, GL_UNSIGNED_BYTE, bitmap->getPixels());
    188         if (glGetError() != GL_NO_ERROR) {
    189             ALOGW("Could not upload to texture");
    190             CLEANUP_GL_AND_RETURN(JNI_FALSE);
    191         }
    192 
    193         // The fence is used to wait for the texture upload to finish
    194         // properly. We cannot rely on glFlush() and glFinish() as
    195         // some drivers completely ignore these API calls
    196         fence = eglCreateSyncKHR(display, EGL_SYNC_FENCE_KHR, NULL);
    197         if (fence == EGL_NO_SYNC_KHR) {
    198             ALOGW("Could not create sync fence %#x", eglGetError());
    199             CLEANUP_GL_AND_RETURN(JNI_FALSE);
    200         }
    201 
    202         // The flag EGL_SYNC_FLUSH_COMMANDS_BIT_KHR will trigger a
    203         // pipeline flush (similar to what a glFlush() would do.)
    204         EGLint waitStatus = eglClientWaitSyncKHR(display, fence,
    205                 EGL_SYNC_FLUSH_COMMANDS_BIT_KHR, FENCE_TIMEOUT);
    206         if (waitStatus != EGL_CONDITION_SATISFIED_KHR) {
    207             ALOGW("Failed to wait for the fence %#x", eglGetError());
    208             CLEANUP_GL_AND_RETURN(JNI_FALSE);
    209         }
    210 
    211         CLEANUP_GL_AND_RETURN(JNI_TRUE);
    212     }
    213 
    214     return JNI_FALSE;
    215 }
    216 
    217 // ----------------------------------------------------------------------------
    218 // JNI Glue
    219 // ----------------------------------------------------------------------------
    220 
    221 #define FIND_CLASS(var, className) \
    222         var = env->FindClass(className); \
    223         LOG_FATAL_IF(! var, "Unable to find class " className);
    224 
    225 #define GET_METHOD_ID(var, clazz, methodName, methodDescriptor) \
    226         var = env->GetMethodID(clazz, methodName, methodDescriptor); \
    227         LOG_FATAL_IF(!var, "Unable to find method " methodName);
    228 
    229 const char* const kClassPathName = "com/android/server/AssetAtlasService";
    230 
    231 static JNINativeMethod gMethods[] = {
    232     { "nAcquireAtlasCanvas", "(Landroid/graphics/Canvas;II)J",
    233             (void*) com_android_server_AssetAtlasService_acquireCanvas },
    234     { "nReleaseAtlasCanvas", "(Landroid/graphics/Canvas;J)V",
    235             (void*) com_android_server_AssetAtlasService_releaseCanvas },
    236     { "nUploadAtlas", "(Landroid/view/GraphicBuffer;J)Z",
    237             (void*) com_android_server_AssetAtlasService_upload },
    238 };
    239 
    240 int register_android_server_AssetAtlasService(JNIEnv* env) {
    241     jclass clazz;
    242 
    243     FIND_CLASS(clazz, "android/graphics/Canvas");
    244     GET_METHOD_ID(gCanvasClassInfo.setNativeBitmap, clazz, "setNativeBitmap", "(J)V");
    245 
    246     return jniRegisterNativeMethods(env, kClassPathName, gMethods, NELEM(gMethods));
    247 }
    248 
    249 };
    250