1 2 /* 3 * Copyright 2011 Google Inc. 4 * 5 * Use of this source code is governed by a BSD-style license that can be 6 * found in the LICENSE file. 7 */ 8 #include "ReaderView.h" 9 #include "SkGPipe.h" 10 #include "SkCanvas.h" 11 12 #include <stdio.h> 13 14 #define FILE_PATH "/Users/yangsu/Code/test/test.a" 15 ReaderView::ReaderView() { 16 fBGColor = 0xFFDDDDDD; 17 fFilePos = 0; 18 fBufferBitmaps[0].setConfig(SkBitmap::kARGB_8888_Config, 640, 480); 19 fBufferBitmaps[0].allocPixels(NULL); 20 fBufferBitmaps[1].setConfig(SkBitmap::kARGB_8888_Config, 640, 480); 21 fBufferBitmaps[1].allocPixels(NULL); 22 fFront = 0; 23 fBack = 1; 24 } 25 26 void ReaderView::draw(SkCanvas* canvas) { 27 canvas->drawColor(fBGColor); 28 29 SkAutoCanvasRestore acr(canvas, true); 30 31 //Create a temporary canvas and reader object that draws into the back 32 //bitmap so that the incremental changes or incomplete reads are not shown 33 //on screen 34 SkCanvas bufferCanvas(fBufferBitmaps[fBack]); 35 SkGPipeReader reader(&bufferCanvas); 36 37 //The file specified by FILE_PATH MUST exist 38 FILE* f = fopen(FILE_PATH, "rb"); 39 SkASSERT(f != NULL); 40 41 fseek(f, 0, SEEK_END); 42 int size = ftell(f) * sizeof(char); 43 if (size <= fFilePos) { 44 fFilePos = 0; 45 } 46 47 //Resume from the last read location 48 fseek(f, fFilePos, SEEK_SET); 49 int toBeRead = size - fFilePos; 50 if (size > 0 && toBeRead > 0) { 51 void* block = sk_malloc_throw(toBeRead); 52 fread(block, 1, toBeRead, f); 53 54 size_t bytesRead; 55 SkGPipeReader::Status fStatus = reader.playback(block, toBeRead, &bytesRead); 56 SkASSERT(SkGPipeReader::kError_Status != fStatus); 57 SkASSERT(toBeRead >= bytesRead); 58 59 //if the reader reaches a done verb, a frame is complete. 60 //Update the file location and swap the front and back bitmaps to show 61 //the new frame 62 if (SkGPipeReader::kDone_Status == fStatus) { 63 fFilePos += bytesRead; 64 fFront = fFront ^ 0x1; 65 fBack = fBack ^ 0x1; 66 } 67 sk_free(block); 68 } 69 70 fclose(f); 71 72 //the front bitmap is always drawn 73 canvas->drawBitmap(fBufferBitmaps[fFront], 0, 0, NULL); 74 this->inval(NULL); 75 } 76
