1 /*
2  * Copyright (C) 2012 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 // Provides a webviewchromium glue layer adapter from the internal Android
18 // graphics types into the types the chromium stack expects, and back.
19 
20 #define LOG_TAG "webviewchromium_plat_support"
21 
22 #include "draw_gl.h"
23 #include "draw_sw.h"
24 
25 #include <cstdlib>
26 #include <jni.h>
27 #include <utils/Log.h>
28 #include "graphic_buffer_impl.h"
29 #include "GraphicsJNI.h"
30 #include "SkCanvasStateUtils.h"
31 #include "SkGraphics.h"
32 #include "SkPicture.h"
33 
34 #define NELEM(x) ((int) (sizeof(x) / sizeof((x)[0])))
35 
36 namespace android {
37 namespace {
38 
39 class PixelInfo : public AwPixelInfo {
40  public:
41   PixelInfo(SkCanvas* canvas);
42   ~PixelInfo();
43 };
44 
45 
PixelInfo(SkCanvas * canvas)46 PixelInfo::PixelInfo(SkCanvas* canvas) {
47   memset(this, 0, sizeof(AwPixelInfo));
48   version = kAwPixelInfoVersion;
49   state = SkCanvasStateUtils::CaptureCanvasState(canvas);
50 }
51 
~PixelInfo()52 PixelInfo::~PixelInfo() {
53   if (state)
54     SkCanvasStateUtils::ReleaseCanvasState(state);
55 }
56 
GetPixels(JNIEnv * env,jobject java_canvas)57 AwPixelInfo* GetPixels(JNIEnv* env, jobject java_canvas) {
58   android::Canvas* nativeCanvas = GraphicsJNI::getNativeCanvas(env, java_canvas);
59   if (!nativeCanvas)
60     return NULL;
61 
62   SkCanvas* canvas = nativeCanvas->asSkCanvas();
63   if (!canvas)
64     return NULL;
65 
66   // Workarounds for http://crbug.com/271096: SW draw only supports
67   // translate & scale transforms, and a simple rectangular clip.
68   // (This also avoids significant wasted time in calling
69   // SkCanvasStateUtils::CaptureCanvasState when the clip is complex).
70   if (!canvas->isClipRect() ||
71       (canvas->getTotalMatrix().getType() &
72                 ~(SkMatrix::kTranslate_Mask | SkMatrix::kScale_Mask))) {
73     return NULL;
74   }
75 
76   PixelInfo* pixels = new PixelInfo(canvas);
77   if (!pixels->state) {
78       delete pixels;
79       pixels = NULL;
80   }
81   return pixels;
82 }
83 
ReleasePixels(AwPixelInfo * pixels)84 void ReleasePixels(AwPixelInfo* pixels) {
85   delete static_cast<PixelInfo*>(pixels);
86 }
87 
GetDrawSWFunctionTable(JNIEnv * env,jclass)88 jlong GetDrawSWFunctionTable(JNIEnv* env, jclass) {
89   static AwDrawSWFunctionTable function_table;
90   function_table.version = kAwDrawSWFunctionTableVersion;
91   function_table.access_pixels = &GetPixels;
92   function_table.release_pixels = &ReleasePixels;
93   return reinterpret_cast<intptr_t>(&function_table);
94 }
95 
GetDrawGLFunctionTable(JNIEnv * env,jclass)96 jlong GetDrawGLFunctionTable(JNIEnv* env, jclass) {
97   static AwDrawGLFunctionTable function_table;
98   function_table.version = kAwDrawGLFunctionTableVersion;
99   function_table.create_graphic_buffer = &GraphicBufferImpl::Create;
100   function_table.release_graphic_buffer = &GraphicBufferImpl::Release;
101   function_table.map = &GraphicBufferImpl::MapStatic;
102   function_table.unmap = &GraphicBufferImpl::UnmapStatic;
103   function_table.get_native_buffer = &GraphicBufferImpl::GetNativeBufferStatic;
104   function_table.get_stride = &GraphicBufferImpl::GetStrideStatic;
105   return reinterpret_cast<intptr_t>(&function_table);
106 }
107 
108 const char kClassName[] = "com/android/webview/chromium/GraphicsUtils";
109 const JNINativeMethod kJniMethods[] = {
110     { "nativeGetDrawSWFunctionTable", "()J",
111         reinterpret_cast<void*>(GetDrawSWFunctionTable) },
112     { "nativeGetDrawGLFunctionTable", "()J",
113         reinterpret_cast<void*>(GetDrawGLFunctionTable) },
114 };
115 
116 }  // namespace
117 
RegisterGraphicsUtils(JNIEnv * env)118 void RegisterGraphicsUtils(JNIEnv* env) {
119   jclass clazz = env->FindClass(kClassName);
120   LOG_ALWAYS_FATAL_IF(!clazz, "Unable to find class '%s'", kClassName);
121 
122   int res = env->RegisterNatives(clazz, kJniMethods, NELEM(kJniMethods));
123   LOG_ALWAYS_FATAL_IF(res < 0, "register native methods failed: res=%d", res);
124 }
125 
126 }  // namespace android
127