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      1 /*
      2  * Copyright (C) 2010 The Android Open Source Project
      3  * Copyright (C) 2012-2013, The Linux Foundation. All rights reserved.
      4  *
      5  * Not a Contribution, Apache license notifications and license are retained
      6  * for attribution purposes only.
      7  *
      8  * Licensed under the Apache License, Version 2.0 (the "License");
      9  * you may not use this file except in compliance with the License.
     10  * You may obtain a copy of the License at
     11  *
     12  *      http://www.apache.org/licenses/LICENSE-2.0
     13  *
     14  * Unless required by applicable law or agreed to in writing, software
     15  * distributed under the License is distributed on an "AS IS" BASIS,
     16  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     17  * See the License for the specific language governing permissions and
     18  * limitations under the License.
     19  */
     20 
     21 #define DEBUG_COPYBIT 0
     22 #include <sync/sync.h>
     23 #include <copybit.h>
     24 #include <utils/Timers.h>
     25 #include "hwc_copybit.h"
     26 #include "comptype.h"
     27 #include "gr.h"
     28 
     29 namespace qhwc {
     30 
     31 struct range {
     32     int current;
     33     int end;
     34 };
     35 struct region_iterator : public copybit_region_t {
     36 
     37     region_iterator(hwc_region_t region) {
     38         mRegion = region;
     39         r.end = region.numRects;
     40         r.current = 0;
     41         this->next = iterate;
     42     }
     43 
     44 private:
     45     static int iterate(copybit_region_t const * self, copybit_rect_t* rect){
     46         if (!self || !rect) {
     47             ALOGE("iterate invalid parameters");
     48             return 0;
     49         }
     50 
     51         region_iterator const* me =
     52                                   static_cast<region_iterator const*>(self);
     53         if (me->r.current != me->r.end) {
     54             rect->l = me->mRegion.rects[me->r.current].left;
     55             rect->t = me->mRegion.rects[me->r.current].top;
     56             rect->r = me->mRegion.rects[me->r.current].right;
     57             rect->b = me->mRegion.rects[me->r.current].bottom;
     58             me->r.current++;
     59             return 1;
     60         }
     61         return 0;
     62     }
     63 
     64     hwc_region_t mRegion;
     65     mutable range r;
     66 };
     67 
     68 void CopyBit::reset() {
     69     mIsModeOn = false;
     70     mCopyBitDraw = false;
     71 }
     72 
     73 bool CopyBit::canUseCopybitForYUV(hwc_context_t *ctx) {
     74     // return true for non-overlay targets
     75     if(ctx->mMDP.hasOverlay) {
     76        return false;
     77     }
     78     return true;
     79 }
     80 
     81 bool CopyBit::canUseCopybitForRGB(hwc_context_t *ctx,
     82                                         hwc_display_contents_1_t *list,
     83                                         int dpy) {
     84     int compositionType = qdutils::QCCompositionType::
     85                                     getInstance().getCompositionType();
     86 
     87     if ((compositionType & qdutils::COMPOSITION_TYPE_C2D) ||
     88         (compositionType & qdutils::COMPOSITION_TYPE_DYN)) {
     89          if(ctx->listStats[dpy].yuvCount) {
     90              //Overlay up & running. Dont use COPYBIT for RGB layers.
     91              return false;
     92          }
     93     }
     94 
     95     if (compositionType & qdutils::COMPOSITION_TYPE_DYN) {
     96         // DYN Composition:
     97         // use copybit, if (TotalRGBRenderArea < threashold * FB Area)
     98         // this is done based on perf inputs in ICS
     99         // TODO: Above condition needs to be re-evaluated in JB
    100         int fbWidth =  ctx->dpyAttr[dpy].xres;
    101         int fbHeight =  ctx->dpyAttr[dpy].yres;
    102         unsigned int fbArea = (fbWidth * fbHeight);
    103         unsigned int renderArea = getRGBRenderingArea(list);
    104             ALOGD_IF (DEBUG_COPYBIT, "%s:renderArea %u, fbArea %u",
    105                                   __FUNCTION__, renderArea, fbArea);
    106         if (renderArea < (mDynThreshold * fbArea)) {
    107             return true;
    108         }
    109     } else if ((compositionType & qdutils::COMPOSITION_TYPE_MDP)) {
    110       // MDP composition, use COPYBIT always
    111       return true;
    112     } else if ((compositionType & qdutils::COMPOSITION_TYPE_C2D)) {
    113       // C2D composition, use COPYBIT
    114       return true;
    115     }
    116     return false;
    117 }
    118 
    119 unsigned int CopyBit::getRGBRenderingArea
    120                                     (const hwc_display_contents_1_t *list) {
    121     //Calculates total rendering area for RGB layers
    122     unsigned int renderArea = 0;
    123     unsigned int w=0, h=0;
    124     for (unsigned int i=0; i<list->numHwLayers; i++) {
    125          private_handle_t *hnd = (private_handle_t *)list->hwLayers[i].handle;
    126          if (hnd) {
    127              if (BUFFER_TYPE_UI == hnd->bufferType) {
    128                  getLayerResolution(&list->hwLayers[i], w, h);
    129                  renderArea += (w*h);
    130              }
    131          }
    132     }
    133     return renderArea;
    134 }
    135 
    136 bool CopyBit::prepare(hwc_context_t *ctx, hwc_display_contents_1_t *list,
    137                                                             int dpy) {
    138 
    139     if(mEngine == NULL) {
    140         // No copybit device found - cannot use copybit
    141         return false;
    142     }
    143     int compositionType = qdutils::QCCompositionType::
    144                                     getInstance().getCompositionType();
    145 
    146     if ((compositionType == qdutils::COMPOSITION_TYPE_GPU) ||
    147         (compositionType == qdutils::COMPOSITION_TYPE_CPU))   {
    148         //GPU/CPU composition, don't change layer composition type
    149         return true;
    150     }
    151 
    152     if(!(validateParams(ctx, list))) {
    153         ALOGE("%s:Invalid Params", __FUNCTION__);
    154         return false;
    155     }
    156 
    157     if(ctx->listStats[dpy].skipCount) {
    158         //GPU will be anyways used
    159         return false;
    160     }
    161 
    162     bool useCopybitForYUV = canUseCopybitForYUV(ctx);
    163     bool useCopybitForRGB = canUseCopybitForRGB(ctx, list, dpy);
    164     LayerProp *layerProp = ctx->layerProp[dpy];
    165     size_t fbLayerIndex = ctx->listStats[dpy].fbLayerIndex;
    166     hwc_layer_1_t *fbLayer = &list->hwLayers[fbLayerIndex];
    167     private_handle_t *fbHnd = (private_handle_t *)fbLayer->handle;
    168 
    169 
    170 
    171     //Allocate render buffers if they're not allocated
    172     if (useCopybitForYUV || useCopybitForRGB) {
    173         int ret = allocRenderBuffers(fbHnd->width,
    174                                      fbHnd->height,
    175                                      fbHnd->format);
    176         if (ret < 0) {
    177             return false;
    178         } else {
    179             mCurRenderBufferIndex = (mCurRenderBufferIndex + 1) %
    180                 NUM_RENDER_BUFFERS;
    181         }
    182     }
    183 
    184 
    185     // numAppLayers-1, as we iterate till 0th layer index
    186     for (int i = ctx->listStats[dpy].numAppLayers-1; i >= 0 ; i--) {
    187         private_handle_t *hnd = (private_handle_t *)list->hwLayers[i].handle;
    188 
    189         if ((hnd->bufferType == BUFFER_TYPE_VIDEO && useCopybitForYUV) ||
    190             (hnd->bufferType == BUFFER_TYPE_UI && useCopybitForRGB)) {
    191             layerProp[i].mFlags |= HWC_COPYBIT;
    192             list->hwLayers[i].compositionType = HWC_OVERLAY;
    193             mCopyBitDraw = true;
    194         } else {
    195             // We currently cannot mix copybit layers with layers marked to
    196             // be drawn on the framebuffer or that are on the layer cache.
    197             mCopyBitDraw = false;
    198             //There is no need to reset layer properties here as we return in
    199             //draw if mCopyBitDraw is false
    200         }
    201     }
    202     return true;
    203 }
    204 
    205 int CopyBit::clear (private_handle_t* hnd, hwc_rect_t& rect)
    206 {
    207     int ret = 0;
    208     copybit_rect_t clear_rect = {rect.left, rect.top,
    209         rect.right,
    210         rect.bottom};
    211 
    212     copybit_image_t buf;
    213     buf.w = ALIGN(getWidth(hnd),32);
    214     buf.h = getHeight(hnd);
    215     buf.format = hnd->format;
    216     buf.base = (void *)hnd->base;
    217     buf.handle = (native_handle_t *)hnd;
    218 
    219     copybit_device_t *copybit = mEngine;
    220     ret = copybit->clear(copybit, &buf, &clear_rect);
    221     return ret;
    222 }
    223 
    224 bool CopyBit::draw(hwc_context_t *ctx, hwc_display_contents_1_t *list,
    225                                                         int dpy, int32_t *fd) {
    226     // draw layers marked for COPYBIT
    227     int retVal = true;
    228     int copybitLayerCount = 0;
    229     LayerProp *layerProp = ctx->layerProp[dpy];
    230 
    231     if(mCopyBitDraw == false) // there is no layer marked for copybit
    232         return false ;
    233 
    234     //render buffer
    235     private_handle_t *renderBuffer = getCurrentRenderBuffer();
    236     if (!renderBuffer) {
    237         ALOGE("%s: Render buffer layer handle is NULL", __FUNCTION__);
    238         return false;
    239     }
    240 
    241     //Wait for the previous frame to complete before rendering onto it
    242     if(mRelFd[0] >=0) {
    243         sync_wait(mRelFd[0], 1000);
    244         close(mRelFd[0]);
    245         mRelFd[0] = -1;
    246     }
    247 
    248     //Clear the visible region on the render buffer
    249     //XXX: Do this only when needed.
    250     hwc_rect_t clearRegion;
    251     getNonWormholeRegion(list, clearRegion);
    252     clear(renderBuffer, clearRegion);
    253     // numAppLayers-1, as we iterate from 0th layer index with HWC_COPYBIT flag
    254     for (int i = 0; i <= (ctx->listStats[dpy].numAppLayers-1); i++) {
    255         hwc_layer_1_t *layer = &list->hwLayers[i];
    256         if(!(layerProp[i].mFlags & HWC_COPYBIT)) {
    257             ALOGD_IF(DEBUG_COPYBIT, "%s: Not Marked for copybit", __FUNCTION__);
    258             continue;
    259         }
    260         int ret = -1;
    261         if (list->hwLayers[i].acquireFenceFd != -1 ) {
    262             // Wait for acquire Fence on the App buffers.
    263             ret = sync_wait(list->hwLayers[i].acquireFenceFd, 1000);
    264             if(ret < 0) {
    265                 ALOGE("%s: sync_wait error!! error no = %d err str = %s",
    266                                     __FUNCTION__, errno, strerror(errno));
    267             }
    268             close(list->hwLayers[i].acquireFenceFd);
    269             list->hwLayers[i].acquireFenceFd = -1;
    270         }
    271         retVal = drawLayerUsingCopybit(ctx, &(list->hwLayers[i]),
    272                                                     renderBuffer, dpy);
    273         copybitLayerCount++;
    274         if(retVal < 0) {
    275             ALOGE("%s : drawLayerUsingCopybit failed", __FUNCTION__);
    276         }
    277     }
    278 
    279     if (copybitLayerCount) {
    280         copybit_device_t *copybit = getCopyBitDevice();
    281         // Async mode
    282         copybit->flush_get_fence(copybit, fd);
    283     }
    284     return true;
    285 }
    286 
    287 int  CopyBit::drawLayerUsingCopybit(hwc_context_t *dev, hwc_layer_1_t *layer,
    288                                      private_handle_t *renderBuffer, int dpy)
    289 {
    290     hwc_context_t* ctx = (hwc_context_t*)(dev);
    291     int err = 0;
    292     if(!ctx) {
    293          ALOGE("%s: null context ", __FUNCTION__);
    294          return -1;
    295     }
    296 
    297     private_handle_t *hnd = (private_handle_t *)layer->handle;
    298     if(!hnd) {
    299         ALOGE("%s: invalid handle", __FUNCTION__);
    300         return -1;
    301     }
    302 
    303     private_handle_t *fbHandle = (private_handle_t *)renderBuffer;
    304     if(!fbHandle) {
    305         ALOGE("%s: Framebuffer handle is NULL", __FUNCTION__);
    306         return -1;
    307     }
    308 
    309     // Set the copybit source:
    310     copybit_image_t src;
    311     src.w = getWidth(hnd);
    312     src.h = getHeight(hnd);
    313     src.format = hnd->format;
    314     src.base = (void *)hnd->base;
    315     src.handle = (native_handle_t *)layer->handle;
    316     src.horiz_padding = src.w - getWidth(hnd);
    317     // Initialize vertical padding to zero for now,
    318     // this needs to change to accomodate vertical stride
    319     // if needed in the future
    320     src.vert_padding = 0;
    321 
    322     // Copybit source rect
    323     hwc_rect_t sourceCrop = layer->sourceCrop;
    324     copybit_rect_t srcRect = {sourceCrop.left, sourceCrop.top,
    325                               sourceCrop.right,
    326                               sourceCrop.bottom};
    327 
    328     // Copybit destination rect
    329     hwc_rect_t displayFrame = layer->displayFrame;
    330     copybit_rect_t dstRect = {displayFrame.left, displayFrame.top,
    331                               displayFrame.right,
    332                               displayFrame.bottom};
    333 
    334     // Copybit dst
    335     copybit_image_t dst;
    336     dst.w = ALIGN(fbHandle->width,32);
    337     dst.h = fbHandle->height;
    338     dst.format = fbHandle->format;
    339     dst.base = (void *)fbHandle->base;
    340     dst.handle = (native_handle_t *)fbHandle;
    341 
    342     copybit_device_t *copybit = mEngine;
    343 
    344     int32_t screen_w        = displayFrame.right - displayFrame.left;
    345     int32_t screen_h        = displayFrame.bottom - displayFrame.top;
    346     int32_t src_crop_width  = sourceCrop.right - sourceCrop.left;
    347     int32_t src_crop_height = sourceCrop.bottom -sourceCrop.top;
    348 
    349     // Copybit dst
    350     float copybitsMaxScale =
    351                       (float)copybit->get(copybit,COPYBIT_MAGNIFICATION_LIMIT);
    352     float copybitsMinScale =
    353                        (float)copybit->get(copybit,COPYBIT_MINIFICATION_LIMIT);
    354 
    355     if((layer->transform == HWC_TRANSFORM_ROT_90) ||
    356                            (layer->transform == HWC_TRANSFORM_ROT_270)) {
    357         //swap screen width and height
    358         int tmp = screen_w;
    359         screen_w  = screen_h;
    360         screen_h = tmp;
    361     }
    362     private_handle_t *tmpHnd = NULL;
    363 
    364     if(screen_w <=0 || screen_h<=0 ||src_crop_width<=0 || src_crop_height<=0 ) {
    365         ALOGE("%s: wrong params for display screen_w=%d src_crop_width=%d \
    366         screen_w=%d src_crop_width=%d", __FUNCTION__, screen_w,
    367                                 src_crop_width,screen_w,src_crop_width);
    368         return -1;
    369     }
    370 
    371     float dsdx = (float)screen_w/src_crop_width;
    372     float dtdy = (float)screen_h/src_crop_height;
    373 
    374     float scaleLimitMax = copybitsMaxScale * copybitsMaxScale;
    375     float scaleLimitMin = copybitsMinScale * copybitsMinScale;
    376     if(dsdx > scaleLimitMax ||
    377         dtdy > scaleLimitMax ||
    378         dsdx < 1/scaleLimitMin ||
    379         dtdy < 1/scaleLimitMin) {
    380         ALOGE("%s: greater than max supported size dsdx=%f dtdy=%f \
    381               scaleLimitMax=%f scaleLimitMin=%f", __FUNCTION__,dsdx,dtdy,
    382                                           scaleLimitMax,1/scaleLimitMin);
    383         return -1;
    384     }
    385     if(dsdx > copybitsMaxScale ||
    386         dtdy > copybitsMaxScale ||
    387         dsdx < 1/copybitsMinScale ||
    388         dtdy < 1/copybitsMinScale){
    389         // The requested scale is out of the range the hardware
    390         // can support.
    391        ALOGE("%s:%d::Need to scale twice dsdx=%f, dtdy=%f,copybitsMaxScale=%f,\
    392                                  copybitsMinScale=%f,screen_w=%d,screen_h=%d \
    393                   src_crop_width=%d src_crop_height=%d",__FUNCTION__,__LINE__,
    394               dsdx,dtdy,copybitsMaxScale,1/copybitsMinScale,screen_w,screen_h,
    395                                               src_crop_width,src_crop_height);
    396 
    397        //Driver makes width and height as even
    398        //that may cause wrong calculation of the ratio
    399        //in display and crop.Hence we make
    400        //crop width and height as even.
    401        src_crop_width  = (src_crop_width/2)*2;
    402        src_crop_height = (src_crop_height/2)*2;
    403 
    404        int tmp_w =  src_crop_width;
    405        int tmp_h =  src_crop_height;
    406 
    407        if (dsdx > copybitsMaxScale || dtdy > copybitsMaxScale ){
    408          tmp_w = src_crop_width*copybitsMaxScale;
    409          tmp_h = src_crop_height*copybitsMaxScale;
    410        }else if (dsdx < 1/copybitsMinScale ||dtdy < 1/copybitsMinScale ){
    411          tmp_w = src_crop_width/copybitsMinScale;
    412          tmp_h = src_crop_height/copybitsMinScale;
    413          tmp_w  = (tmp_w/2)*2;
    414          tmp_h = (tmp_h/2)*2;
    415        }
    416        ALOGE("%s:%d::tmp_w = %d,tmp_h = %d",__FUNCTION__,__LINE__,tmp_w,tmp_h);
    417 
    418        int usage = GRALLOC_USAGE_PRIVATE_IOMMU_HEAP;
    419 
    420        if (0 == alloc_buffer(&tmpHnd, tmp_w, tmp_h, fbHandle->format, usage)){
    421             copybit_image_t tmp_dst;
    422             copybit_rect_t tmp_rect;
    423             tmp_dst.w = tmp_w;
    424             tmp_dst.h = tmp_h;
    425             tmp_dst.format = tmpHnd->format;
    426             tmp_dst.handle = tmpHnd;
    427             tmp_dst.horiz_padding = src.horiz_padding;
    428             tmp_dst.vert_padding = src.vert_padding;
    429             tmp_rect.l = 0;
    430             tmp_rect.t = 0;
    431             tmp_rect.r = tmp_dst.w;
    432             tmp_rect.b = tmp_dst.h;
    433             //create one clip region
    434             hwc_rect tmp_hwc_rect = {0,0,tmp_rect.r,tmp_rect.b};
    435             hwc_region_t tmp_hwc_reg = {1,(hwc_rect_t const*)&tmp_hwc_rect};
    436             region_iterator tmp_it(tmp_hwc_reg);
    437             copybit->set_parameter(copybit,COPYBIT_TRANSFORM,0);
    438             //TODO: once, we are able to read layer alpha, update this
    439             copybit->set_parameter(copybit, COPYBIT_PLANE_ALPHA, 255);
    440             err = copybit->stretch(copybit,&tmp_dst, &src, &tmp_rect,
    441                                                            &srcRect, &tmp_it);
    442             if(err < 0){
    443                 ALOGE("%s:%d::tmp copybit stretch failed",__FUNCTION__,
    444                                                              __LINE__);
    445                 if(tmpHnd)
    446                     free_buffer(tmpHnd);
    447                 return err;
    448             }
    449             // copy new src and src rect crop
    450             src = tmp_dst;
    451             srcRect = tmp_rect;
    452       }
    453     }
    454     // Copybit region
    455     hwc_region_t region = layer->visibleRegionScreen;
    456     region_iterator copybitRegion(region);
    457 
    458     copybit->set_parameter(copybit, COPYBIT_FRAMEBUFFER_WIDTH,
    459                                           renderBuffer->width);
    460     copybit->set_parameter(copybit, COPYBIT_FRAMEBUFFER_HEIGHT,
    461                                           renderBuffer->height);
    462     copybit->set_parameter(copybit, COPYBIT_TRANSFORM,
    463                                               layer->transform);
    464     //TODO: once, we are able to read layer alpha, update this
    465     copybit->set_parameter(copybit, COPYBIT_PLANE_ALPHA, 255);
    466     copybit->set_parameter(copybit, COPYBIT_BLEND_MODE,
    467                                               layer->blending);
    468     copybit->set_parameter(copybit, COPYBIT_DITHER,
    469                              (dst.format == HAL_PIXEL_FORMAT_RGB_565)?
    470                                              COPYBIT_ENABLE : COPYBIT_DISABLE);
    471     copybit->set_parameter(copybit, COPYBIT_BLIT_TO_FRAMEBUFFER,
    472                                                 COPYBIT_ENABLE);
    473     err = copybit->stretch(copybit, &dst, &src, &dstRect, &srcRect,
    474                                                    &copybitRegion);
    475     copybit->set_parameter(copybit, COPYBIT_BLIT_TO_FRAMEBUFFER,
    476                                                COPYBIT_DISABLE);
    477 
    478     if(tmpHnd)
    479         free_buffer(tmpHnd);
    480 
    481     if(err < 0)
    482         ALOGE("%s: copybit stretch failed",__FUNCTION__);
    483     return err;
    484 }
    485 
    486 void CopyBit::getLayerResolution(const hwc_layer_1_t* layer,
    487                                  unsigned int& width, unsigned int& height)
    488 {
    489     hwc_rect_t displayFrame  = layer->displayFrame;
    490 
    491     width = displayFrame.right - displayFrame.left;
    492     height = displayFrame.bottom - displayFrame.top;
    493 }
    494 
    495 bool CopyBit::validateParams(hwc_context_t *ctx,
    496                                         const hwc_display_contents_1_t *list) {
    497     //Validate parameters
    498     if (!ctx) {
    499         ALOGE("%s:Invalid HWC context", __FUNCTION__);
    500         return false;
    501     } else if (!list) {
    502         ALOGE("%s:Invalid HWC layer list", __FUNCTION__);
    503         return false;
    504     }
    505     return true;
    506 }
    507 
    508 
    509 int CopyBit::allocRenderBuffers(int w, int h, int f)
    510 {
    511     int ret = 0;
    512     for (int i = 0; i < NUM_RENDER_BUFFERS; i++) {
    513         if (mRenderBuffer[i] == NULL) {
    514             ret = alloc_buffer(&mRenderBuffer[i],
    515                                w, h, f,
    516                                GRALLOC_USAGE_PRIVATE_IOMMU_HEAP);
    517         }
    518         if(ret < 0) {
    519             freeRenderBuffers();
    520             break;
    521         }
    522     }
    523     return ret;
    524 }
    525 
    526 void CopyBit::freeRenderBuffers()
    527 {
    528     for (int i = 0; i < NUM_RENDER_BUFFERS; i++) {
    529         if(mRenderBuffer[i]) {
    530             free_buffer(mRenderBuffer[i]);
    531             mRenderBuffer[i] = NULL;
    532         }
    533     }
    534 }
    535 
    536 private_handle_t * CopyBit::getCurrentRenderBuffer() {
    537     return mRenderBuffer[mCurRenderBufferIndex];
    538 }
    539 
    540 void CopyBit::setReleaseFd(int fd) {
    541     if(mRelFd[0] >=0)
    542         close(mRelFd[0]);
    543     mRelFd[0] = mRelFd[1];
    544     mRelFd[1] = dup(fd);
    545 }
    546 
    547 struct copybit_device_t* CopyBit::getCopyBitDevice() {
    548     return mEngine;
    549 }
    550 
    551 CopyBit::CopyBit():mIsModeOn(false), mCopyBitDraw(false),
    552     mCurRenderBufferIndex(0){
    553     hw_module_t const *module;
    554     for (int i = 0; i < NUM_RENDER_BUFFERS; i++)
    555         mRenderBuffer[i] = NULL;
    556     mRelFd[0] = -1;
    557     mRelFd[1] = -1;
    558 
    559     char value[PROPERTY_VALUE_MAX];
    560     property_get("debug.hwc.dynThreshold", value, "2");
    561     mDynThreshold = atof(value);
    562 
    563     if (hw_get_module(COPYBIT_HARDWARE_MODULE_ID, &module) == 0) {
    564         if(copybit_open(module, &mEngine) < 0) {
    565             ALOGE("FATAL ERROR: copybit open failed.");
    566         }
    567     } else {
    568         ALOGE("FATAL ERROR: copybit hw module not found");
    569     }
    570 }
    571 
    572 CopyBit::~CopyBit()
    573 {
    574     freeRenderBuffers();
    575     if(mRelFd[0] >=0)
    576         close(mRelFd[0]);
    577     if(mRelFd[1] >=0)
    578         close(mRelFd[1]);
    579     if(mEngine)
    580     {
    581         copybit_close(mEngine);
    582         mEngine = NULL;
    583     }
    584 }
    585 }; //namespace qhwc
    586