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cairo-beos-surface.cpp

/* vim:set ts=8 sw=4 noet cin: */
/* cairo - a vector graphics library with display and print output
 *
 * Copyright © 2005 Christian Biesinger <cbiesinger@web.de>
 *
 * This library is free software; you can redistribute it and/or
 * modify it either under the terms of the GNU Lesser General Public
 * License version 2.1 as published by the Free Software Foundation
 * (the "LGPL") or, at your option, under the terms of the Mozilla
 * Public License Version 1.1 (the "MPL"). If you do not alter this
 * notice, a recipient may use your version of this file under either
 * the MPL or the LGPL.
 *
 * You should have received a copy of the LGPL along with this library
 * in the file COPYING-LGPL-2.1; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA
 * You should have received a copy of the MPL along with this library
 * in the file COPYING-MPL-1.1
 *
 * The contents of this file are subject to the Mozilla Public License
 * Version 1.1 (the "License"); you may not use this file except in
 * compliance with the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
 * OF ANY KIND, either express or implied. See the LGPL or the MPL for
 * the specific language governing rights and limitations.
 *
 * The Original Code is the cairo graphics library.
 *
 * The Initial Developer of the Original Code is Christian Biesinger
 * <cbiesinger@web.de>
 *
 * Contributor(s):
 */

// This is a C++ file in order to use the C++ BeOS API

#include "cairoint.h"

#include "cairo-beos.h"

#include "cairo-error-private.h"

#include <new>

#include <Bitmap.h>
#include <Region.h>
#if 0
#include <DirectWindow.h>
#endif
#include <Screen.h>
#include <Window.h>
#include <Locker.h>

/**
 * SECTION:beos-surface
 * @Title: BeOS Surfaces
 * @Short_Description: BeOS surface support
 * @See_Also: #cairo_surface_t
 *
 * The BeOS surface is used to render cairo graphics to BeOS views 
 * and bitmaps.
 */

#define CAIRO_INT_STATUS_SUCCESS (cairo_int_status_t)(CAIRO_STATUS_SUCCESS)

00068 struct cairo_beos_surface_t {
    cairo_surface_t base;

    cairo_region_t *clip_region;

    BView* view;

    /*
     * A view is either attached to a bitmap, a window, or unattached.
     * If it is attached to a window, we can copy data out of it using BScreen.
     * If it is attached to a bitmap, we can read the bitmap data.
     * If it is not attached, it doesn't draw anything, we need not bother.
     *
     * Since there doesn't seem to be a way to get the bitmap from a view if it
     * is attached to one, we have to use a special surface creation function.
     */

    BBitmap* bitmap;

    // If true, surface and view should be deleted when this surface is
    // destroyed
    bool owns_bitmap_view;
};

00092 class AutoLockView {
    public:
      AutoLockView(BView* view) : mView(view) {
          mOK = mView->LockLooper();
      }

      ~AutoLockView() {
          if (mOK)
            mView->UnlockLooper();
      }

      operator bool() {
          return mOK;
      }

    private:
      BView* mView;
      bool   mOK;
};

static cairo_surface_t *
_cairo_beos_surface_create_internal (BView*   view,
                             BBitmap* bmp,
                             bool     owns_bitmap_view = false);

static inline BRect
_cairo_rectangle_to_brect (const cairo_rectangle_int_t* rect)
{
    // A BRect is one pixel wider than you'd think
    return BRect (rect->x, rect->y,
              rect->x + rect->width - 1,
              rect->y + rect->height - 1);
}

static inline cairo_rectangle_int_t
_brect_to_cairo_rectangle (const BRect &rect)
{
    cairo_rectangle_int_t retval;
    retval.x = floor (rect.left);
    retval.y = floor (rect.top);
    retval.width = ceil (rect.right) - retval.x + 1;
    retval.height = ceil (rect.bottom) - rectval.y + 1;
    return retval;
}

static inline rgb_color
_cairo_color_to_be_color (const cairo_color_t *color)
{
    // This factor ensures a uniform distribution of numbers
    const float factor = 256 - 1e-5;
    // Using doubles to have non-premultiplied colors
    rgb_color be_color = { uint8(color->red * factor),
                     uint8(color->green * factor),
                     uint8(color->blue * factor),
                     uint8(color->alpha * factor) };

    return be_color;
}

enum ViewCopyStatus {
    OK,
    NOT_VISIBLE, // The view or the interest rect is not visible on screen
    ERROR        // The view was visible, but the rect could not be copied. Probably OOM
};

/**
 * _cairo_beos_view_to_bitmap:
 * @bitmap: [out] The resulting bitmap.
 * @rect: [out] The rectangle that was copied, in the view's coordinate system
 * @interestRect: If non-null, only this part of the view will be copied (view's coord system).
 *
 * Gets the contents of the view as a BBitmap*. Caller must delete the bitmap.
 **/
static ViewCopyStatus
_cairo_beos_view_to_bitmap (BView*       view,
                      BBitmap**    bitmap,
                      BRect*       rect = NULL,
                      const BRect* interestRect = NULL)
{
    *bitmap = NULL;

    BWindow* wnd = view->Window();
    // If we have no window, can't do anything
    if (!wnd)
      return NOT_VISIBLE;

    view->Sync();
    wnd->Sync();

#if 0
    // Is it a direct window?
    BDirectWindow* directWnd = dynamic_cast<BDirectWindow*>(wnd);
    if (directWnd) {
      // WRITEME
    }
#endif

    // Is it visible? If so, we can copy the content off the screen
    if (wnd->IsHidden())
      return NOT_VISIBLE;

    BRect rectToCopy(view->Bounds());
    if (interestRect)
      rectToCopy = rectToCopy & *interestRect;

    if (!rectToCopy.IsValid())
      return NOT_VISIBLE;

    BScreen screen(wnd);
    BRect screenRect(view->ConvertToScreen(rectToCopy));
    screenRect = screenRect & screen.Frame();

    if (!screen.IsValid())
      return NOT_VISIBLE;

    if (rect)
      *rect = view->ConvertFromScreen(screenRect);

    if (screen.GetBitmap(bitmap, false, &screenRect) == B_OK)
      return OK;

    return ERROR;
}

static void
unpremultiply_bgra (unsigned char* data,
                int            width,
                int            height,
                int            stride,
                unsigned char* retdata)
{
    unsigned char* end = data + stride * height;
    for (unsigned char* in = data, *out = retdata;
       in < end;
       in += stride, out += stride)
    {
      for (int i = 0; i < width; i ++) {
          uint8_t *b = &out[4*i];
          uint32_t pixel;
          uint8_t  alpha;

          memcpy (&pixel, &data[4*i], sizeof (uint32_t));
          alpha = pixel & 0xff;
          if (alpha == 0) {
            b[0] = b[1] = b[2] = b[3] = 0;
          } else {
            b[0] = (((pixel >> 24) & 0xff) * 255 + alpha / 2) / alpha;
            b[1] = (((pixel >> 16) & 0xff) * 255 + alpha / 2) / alpha;
            b[2] = (((pixel >>  8) & 0xff) * 255 + alpha / 2) / alpha;
            b[3] = alpha;
          }
      }
    }
}

static inline int
multiply_alpha (int alpha, int color)
{
    int temp = (alpha * color) + 0x80;
    return ((temp + (temp >> 8)) >> 8);
}

static unsigned char*
premultiply_bgra (unsigned char* data,
              int            width,
              int            height,
              int            stride)
{
    uint8_t * retdata = reinterpret_cast<unsigned char*>(_cairo_malloc_ab(height, stride));
    if (!retdata)
      return NULL;

    uint8_t * end = data + stride * height;
    for (uint8_t * in = data, *out = retdata;
       in < end;
       in += stride, out += stride)
    {
      for (int i = 0; i < width; i ++) {
          uint8_t *base  = &in[4*i];
          uint8_t  alpha = base[3];
          uint32_t p;

          if (alpha == 0) {
            p = 0;
          } else {
            uint8_t  blue  = base[0];
            uint8_t  green = base[1];
            uint8_t  red   = base[2];

            if (alpha != 0xff) {
                blue  = multiply_alpha (alpha, blue);
                green = multiply_alpha (alpha, green);
                red   = multiply_alpha (alpha, red);
            }
            p = (alpha << 0) | (red << 8) | (green << 16) | (blue << 24);
          }
          memcpy (&out[4*i], &p, sizeof (uint32_t));
      }
    }
    return retdata;
}

static cairo_int_status_t
_cairo_beos_surface_set_clip_region (cairo_beos_surface_t *surface,
                             cairo_region_t     *region)
{
    cairo_beos_surface_t *surface = reinterpret_cast<cairo_beos_surface_t*>(
                                          abstract_surface);
    AutoLockView locker(surface->view);
    assert (locker);

    if (region == surface->clip_region)
      return CAIRO_INT_STATUS_SUCCESS;

    cairo_region_destroy (surface->clip_region);
    surface->clip_region = cairo_region_reference (region);

    if (region == NULL) {
      // No clipping
      surface->view->ConstrainClippingRegion(NULL);
      return CAIRO_INT_STATUS_SUCCESS;
    }

    int count = cairo_region_num_rectangles (region);
    BRegion bregion;
    for (int i = 0; i < count; ++i) {
      cairo_rectangle_int_t rect;

      cairo_region_get_rectangle (region, i, &rect);
      // Have to substract one, because for pixman, the second coordinate
      // lies outside the rectangle.
      bregion.Include (_cairo_rectangle_to_brect (&rect));
    }
    surface->view->ConstrainClippingRegion(&bregion);
    return CAIRO_INT_STATUS_SUCCESS;
}


/**
 * _cairo_beos_bitmap_to_surface:
 *
 * Returns an addrefed image surface for a BBitmap. The bitmap need not outlive
 * the surface.
 **/
static cairo_image_surface_t*
_cairo_beos_bitmap_to_surface (BBitmap* bitmap)
{
    color_space format = bitmap->ColorSpace();
    if (format != B_RGB32 && format != B_RGBA32) {
      BBitmap bmp(bitmap->Bounds(), B_RGB32, true);
      BView view(bitmap->Bounds(), "Cairo bitmap drawing view",
               B_FOLLOW_ALL_SIDES, 0);
      bmp.AddChild(&view);

      view.LockLooper();

      view.DrawBitmap(bitmap, BPoint(0.0, 0.0));
      view.Sync();

      cairo_image_surface_t* imgsurf = _cairo_beos_bitmap_to_surface(&bmp);

      view.UnlockLooper();
      bmp.RemoveChild(&view);
      return imgsurf;
    }

    cairo_format_t cformat = format == B_RGB32 ?
                           CAIRO_FORMAT_RGB24 : CAIRO_FORMAT_ARGB32;

    BRect bounds(bitmap->Bounds());
    unsigned char* bits = reinterpret_cast<unsigned char*>(bitmap->Bits());
    int width = bounds.IntegerWidth() + 1;
    int height = bounds.IntegerHeight() + 1;
    unsigned char* premultiplied;
    if (cformat == CAIRO_FORMAT_ARGB32) {
       premultiplied = premultiply_bgra (bits, width, height,
                               bitmap->BytesPerRow());
    } else {
      premultiplied = reinterpret_cast<unsigned char*>(
                              _cairo_malloc_ab(bitmap->BytesPerRow(), height));
      if (premultiplied)
          memcpy(premultiplied, bits, bitmap->BytesPerRow() * height);
    }
    if (!premultiplied)
      return _cairo_surface_create_in_error (_cairo_error (CAIRO_STATUS_NO_MEMORY));

    cairo_image_surface_t* surf = reinterpret_cast<cairo_image_surface_t*>
      (cairo_image_surface_create_for_data(premultiplied,
                                   cformat,
                                   width,
                                   height,
                                   bitmap->BytesPerRow()));
    if (surf->base.status)
      free(premultiplied);
    else
      _cairo_image_surface_assume_ownership_of_data(surf);
    return surf;
}

/**
 * _cairo_image_surface_to_bitmap:
 *
 * Converts an image surface to a BBitmap. The return value must be freed with
 * delete.
 **/
static BBitmap*
_cairo_image_surface_to_bitmap (cairo_image_surface_t* surface)
{
    BRect size(0.0, 0.0, surface->width - 1, surface->height - 1);
    switch (surface->format) {
      case CAIRO_FORMAT_ARGB32: {
          BBitmap* data = new BBitmap(size, B_RGBA32);
          unpremultiply_bgra (surface->data,
                        surface->width,
                        surface->height,
                        surface->stride,
                        reinterpret_cast<unsigned char*>(data->Bits()));
          return data;
        }
      case CAIRO_FORMAT_RGB24: {
          BBitmap* data = new BBitmap(size, B_RGB32);
          memcpy(data->Bits(), surface->data, surface->height * surface->stride);
          return data;
      }
      default:
          assert(0);
          return NULL;
    }
}

/**
 * _cairo_op_to_be_op:
 *
 * Converts a cairo drawing operator to a beos drawing_mode. Returns true if
 * the operator could be converted, false otherwise.
 **/
static bool
_cairo_op_to_be_op (cairo_operator_t cairo_op,
                drawing_mode*    beos_op)
{
    switch (cairo_op) {
    case CAIRO_OPERATOR_SOURCE:
      *beos_op = B_OP_COPY;
      return true;
    case CAIRO_OPERATOR_OVER:
      *beos_op = B_OP_ALPHA;
      return true;

    case CAIRO_OPERATOR_ADD:
      // Does not actually work
      // XXX This is a fundamental compositing operator, it has to work!
#if 1
      return false;
#else
      *beos_op = B_OP_ADD;
      return true;
#endif

    case CAIRO_OPERATOR_CLEAR:
      // Does not map to B_OP_ERASE - it replaces the dest with the low
      // color, instead of transparency; could be done by setting low
      // color appropriately.

    case CAIRO_OPERATOR_IN:
    case CAIRO_OPERATOR_OUT:
    case CAIRO_OPERATOR_ATOP:

    case CAIRO_OPERATOR_DEST:
    case CAIRO_OPERATOR_DEST_OVER:
    case CAIRO_OPERATOR_DEST_IN:
    case CAIRO_OPERATOR_DEST_OUT:
    case CAIRO_OPERATOR_DEST_ATOP:

    case CAIRO_OPERATOR_XOR:
    case CAIRO_OPERATOR_SATURATE:

    default:
      return false;
    }
}

static cairo_surface_t *
_cairo_beos_surface_create_similar (void            *abstract_surface,
                            cairo_content_t  content,
                            int              width,
                            int              height)
{
    cairo_beos_surface_t *surface = reinterpret_cast<cairo_beos_surface_t*>(
                                          abstract_surface);

    if (width <= 0)
      width = 1;
    if (height <= 0)
      height = 1;

    BRect rect(0.0, 0.0, width - 1, height - 1);
    BBitmap* bmp;
    switch (content) {
      case CAIRO_CONTENT_ALPHA:
          return NULL;
      case CAIRO_CONTENT_COLOR_ALPHA:
          bmp = new BBitmap(rect, B_RGBA32, true);
          break;
      case CAIRO_CONTENT_COLOR:
          // Match the color depth
          if (surface->bitmap) {
            color_space space = surface->bitmap->ColorSpace();
            // No alpha was requested -> make sure not to return
            // a surface with alpha
            if (space == B_RGBA32)
                space = B_RGB32;
            if (space == B_RGBA15)
                space = B_RGB15;
            bmp = new BBitmap(rect, space, true);
          } else {
            BScreen scr(surface->view->Window());
            color_space space = B_RGB32;
            if (scr.IsValid())
                space = scr.ColorSpace();
            bmp = new BBitmap(rect, space, true);
          }
          break;
      default:
          ASSERT_NOT_REACHED;
          return NULL;
    }
    BView* view = new BView(rect, "Cairo bitmap view", B_FOLLOW_ALL_SIDES, 0);
    bmp->AddChild(view);
    return _cairo_beos_surface_create_internal(view, bmp, true);
}

static cairo_status_t
_cairo_beos_surface_finish (void *abstract_surface)
{
    cairo_beos_surface_t *surface = reinterpret_cast<cairo_beos_surface_t*>(
                                          abstract_surface);
    if (surface->owns_bitmap_view) {
      if (surface->bitmap)
          surface->bitmap->RemoveChild(surface->view);

      delete surface->view;
      delete surface->bitmap;

      surface->view = NULL;
      surface->bitmap = NULL;
    }

    cairo_region_destroy (surface->clip_region);

    return CAIRO_STATUS_SUCCESS;
}

static cairo_status_t
_cairo_beos_surface_acquire_source_image (void                   *abstract_surface,
                                cairo_image_surface_t **image_out,
                                void                  **image_extra)
{
    cairo_beos_surface_t *surface = reinterpret_cast<cairo_beos_surface_t*>(
                                          abstract_surface);
    AutoLockView locker(surface->view);
    if (!locker)
      return CAIRO_STATUS_NO_MEMORY; /// XXX not exactly right, but what can we do?


    surface->view->Sync();

    if (surface->bitmap) {
      *image_out = _cairo_beos_bitmap_to_surface (surface->bitmap);
      if (unlikely ((*image_out)->base.status))
          return (*image_out)->base.status;

      *image_extra = NULL;
      return CAIRO_STATUS_SUCCESS;
    }

    BBitmap* bmp;
    if (_cairo_beos_view_to_bitmap(surface->view, &bmp) != OK)
      return CAIRO_STATUS_NO_MEMORY; /// XXX incorrect if the error was NOT_VISIBLE

    *image_out = _cairo_beos_bitmap_to_surface (bmp);
    if (unlikely ((*image_out)->base.status)) {
      delete bmp;
      return (*image_out)->base.status;
    }
    *image_extra = bmp;

    return CAIRO_STATUS_SUCCESS;
}

static void
_cairo_beos_surface_release_source_image (void                  *abstract_surface,
                                cairo_image_surface_t *image,
                                void                  *image_extra)
{
    cairo_surface_destroy (&image->base);

    if (image_extra != NULL) {
      BBitmap* bmp = static_cast<BBitmap*>(image_extra);
      delete bmp;
    }
}

static cairo_status_t
_cairo_beos_surface_acquire_dest_image (void                 *abstract_surface,
                                        cairo_rectangle_int_t      *interest_rect,
                                        cairo_image_surface_t     **image_out,
                                        cairo_rectangle_int_t      *image_rect,
                                        void                **image_extra)
{
    cairo_beos_surface_t *surface = reinterpret_cast<cairo_beos_surface_t*>(
                                          abstract_surface);

    AutoLockView locker(surface->view);
    if (!locker) {
      *image_out = NULL;
      *image_extra = NULL;
      return (cairo_status_t) CAIRO_INT_STATUS_NOTHING_TO_DO;
    }

    if (surface->bitmap) {
      surface->view->Sync();
      *image_out = _cairo_beos_bitmap_to_surface(surface->bitmap);
      if (unlikely ((*image_out)->base.status))
          return (*image_out)->base.status;

      image_rect->x = 0;
      image_rect->y = 0;
      image_rect->width = (*image_out)->width;
      image_rect->height = (*image_out)->height;

      *image_extra = NULL;
      return CAIRO_STATUS_SUCCESS;
    }

    BRect b_interest_rect (_cairo_rectangle_to_brect (interest_rect));

    BRect rect;
    BBitmap* bitmap;
    ViewCopyStatus status = _cairo_beos_view_to_bitmap(surface->view, &bitmap,
                                                     &rect, &b_interest_rect);
    if (status == NOT_VISIBLE) {
      *image_out = NULL;
      *image_extra = NULL;
      return CAIRO_STATUS_SUCCESS;
    }
    if (status == ERROR)
      return CAIRO_STATUS_NO_MEMORY;

    *image_rect = _brect_to_cairo_rectangle(rect);
    *image_out = _cairo_beos_bitmap_to_surface(bitmap);
    delete bitmap;
    if (unlikely ((*image_out)->base.status))
      return (*image_out)->base.status;

    *image_extra = NULL;

    return CAIRO_STATUS_SUCCESS;
}


static void
_cairo_beos_surface_release_dest_image (void                *abstract_surface,
                                        cairo_rectangle_int_t     *intersect_rect,
                                        cairo_image_surface_t     *image,
                                        cairo_rectangle_int_t     *image_rect,
                                        void                *image_extra)
{
    cairo_beos_surface_t *surface = reinterpret_cast<cairo_beos_surface_t*>(
                                          abstract_surface);

    AutoLockView locker(surface->view);
    if (!locker)
      return;

    BBitmap* bitmap_to_draw = _cairo_image_surface_to_bitmap(image);
    surface->view->PushState();

      surface->view->SetDrawingMode(B_OP_COPY);

      surface->view->DrawBitmap (bitmap_to_draw,
                           _cairo_rectangle_to_brect (image_rect));

    surface->view->PopState();

    delete bitmap_to_draw;
    cairo_surface_destroy(&image->base);
}

static cairo_int_status_t
_cairo_beos_surface_composite (cairo_operator_t       op,
                         cairo_pattern_t         *src,
                         cairo_pattern_t         *mask,
                         void              *dst,
                         int              src_x,
                         int              src_y,
                         int              mask_x,
                         int              mask_y,
                         int              dst_x,
                         int              dst_y,
                         unsigned int           width,
                         unsigned int           height,
                         cairo_region_t         *clip_region)
{
    cairo_beos_surface_t *surface = reinterpret_cast<cairo_beos_surface_t*>(
                                          dst);
    cairo_int_status_t status;
    AutoLockView locker(surface->view);
    if (!locker)
      return CAIRO_INT_STATUS_SUCCESS;

    drawing_mode mode;
    if (!_cairo_op_to_be_op(op, &mode))
      return CAIRO_INT_STATUS_UNSUPPORTED;

    // XXX Masks are not yet supported
    if (mask)
      return CAIRO_INT_STATUS_UNSUPPORTED;

    // XXX should eventually support the others
    if (src->type != CAIRO_PATTERN_TYPE_SURFACE ||
      src->extend != CAIRO_EXTEND_NONE)
    {
      return CAIRO_INT_STATUS_UNSUPPORTED;
    }

    // Can we maybe support other matrices as well? (scale? if the filter is right)
    int itx, ity;
    if (!_cairo_matrix_is_integer_translation(&src->matrix, &itx, &ity))
      return CAIRO_INT_STATUS_UNSUPPORTED;

    status = _cairo_beos_surface_set_clip_region (surface, clip_region);
    if (unlikely (status))
      return status;

    BRect srcRect(src_x + itx,
              src_y + ity,
              src_x + itx + width - 1,
              src_y + ity + height - 1);
    BRect dstRect(dst_x, dst_y, dst_x + width - 1, dst_y + height - 1);

    cairo_surface_t* src_surface = reinterpret_cast<cairo_surface_pattern_t*>(src)->
                              surface;

    // Get a bitmap
    BBitmap* bmp = NULL;
    bool free_bmp = false;
    if (_cairo_surface_is_image(src_surface)) {
      cairo_image_surface_t* img_surface =
          reinterpret_cast<cairo_image_surface_t*>(src_surface);

      bmp = _cairo_image_surface_to_bitmap(img_surface);
      free_bmp = true;
    } else if (src_surface->backend == surface->base.backend) {
      cairo_beos_surface_t *beos_surface =
          reinterpret_cast<cairo_beos_surface_t*>(src_surface);
      if (beos_surface->bitmap) {
          AutoLockView locker(beos_surface->view);
          if (locker)
            beos_surface->view->Sync();
          bmp = beos_surface->bitmap;
      } else {
          _cairo_beos_view_to_bitmap(surface->view, &bmp);
          free_bmp = true;
      }
    }

    if (!bmp)
      return CAIRO_INT_STATUS_UNSUPPORTED;

    // So, BeOS seems to screw up painting an opaque bitmap onto a
    // translucent one (it makes them partly transparent). Just return
    // unsupported.
    if (bmp->ColorSpace() == B_RGB32 && surface->bitmap &&
      surface->bitmap->ColorSpace() == B_RGBA32 &&
      (mode == B_OP_COPY || mode == B_OP_ALPHA))
    {
      if (free_bmp)
          delete bmp;
      return CAIRO_INT_STATUS_UNSUPPORTED;
    }

    // Draw it on screen.
    surface->view->PushState();

      // If our image rect is only a subrect of the desired size, and we
      // aren't using B_OP_ALPHA, then we need to fill the rect first.
      if (mode == B_OP_COPY && !bmp->Bounds().Contains(srcRect)) {
          rgb_color black = { 0, 0, 0, 0 };

          surface->view->SetDrawingMode(mode);
          surface->view->SetHighColor(black);
          surface->view->FillRect(dstRect);
      }

      if (mode == B_OP_ALPHA && bmp->ColorSpace() == B_RGB32) {
          mode = B_OP_COPY;
      }
      surface->view->SetDrawingMode(mode);

      if (surface->bitmap && surface->bitmap->ColorSpace() == B_RGBA32)
          surface->view->SetBlendingMode(B_PIXEL_ALPHA, B_ALPHA_COMPOSITE);
      else
          surface->view->SetBlendingMode(B_PIXEL_ALPHA, B_ALPHA_OVERLAY);

      surface->view->DrawBitmap(bmp, srcRect, dstRect);

    surface->view->PopState();

    if (free_bmp)
      delete bmp;

    return CAIRO_INT_STATUS_SUCCESS;
}


static cairo_int_status_t
_cairo_beos_surface_fill_rectangles (void             *abstract_surface,
                             cairo_operator_t          op,
                             const cairo_color_t      *color,
                             cairo_rectangle_int_t    *rects,
                             int                 num_rects,
                             cairo_region_t           *clip_region)
{
    cairo_beos_surface_t *surface = reinterpret_cast<cairo_beos_surface_t*>(
                                          abstract_surface);
    cairo_int_status_t status;

    if (num_rects <= 0)
      return CAIRO_INT_STATUS_SUCCESS;

    AutoLockView locker(surface->view);
    if (!locker)
      return CAIRO_INT_STATUS_SUCCESS;

    drawing_mode mode;
    if (!_cairo_op_to_be_op(op, &mode))
      return CAIRO_INT_STATUS_UNSUPPORTED;

    status = _cairo_beos_surface_set_clip_region (surface, clip_region);
    if (unlikely (status))
      return status;

    rgb_color be_color = _cairo_color_to_be_color(color);

    if (mode == B_OP_ALPHA && be_color.alpha == 0xFF)
      mode = B_OP_COPY;

    // For CAIRO_OPERATOR_SOURCE, cairo expects us to use the premultiplied
    // color info. This is only relevant when drawing into an rgb24 buffer
    // (as for others, we can convert when asked for the image)
    if (mode == B_OP_COPY && be_color.alpha != 0xFF &&
      (!surface->bitmap || surface->bitmap->ColorSpace() != B_RGBA32))
    {
      be_color.red   = color->red_short  >> 8;
      be_color.green = color->green_short >> 8;
      be_color.blue  = color->blue_short  >> 8;
    }

    surface->view->PushState();

      surface->view->SetDrawingMode(mode);
      surface->view->SetHighColor(be_color);
      if (surface->bitmap && surface->bitmap->ColorSpace() == B_RGBA32)
          surface->view->SetBlendingMode(B_CONSTANT_ALPHA, B_ALPHA_COMPOSITE);
      else
          surface->view->SetBlendingMode(B_CONSTANT_ALPHA, B_ALPHA_OVERLAY);

      for (int i = 0; i < num_rects; ++i)
          surface->view->FillRect (_cairo_rectangle_to_brect (&rects[i]));

    surface->view->PopState();

    return CAIRO_INT_STATUS_SUCCESS;
}

static cairo_bool_t
_cairo_beos_surface_get_extents (void                       *abstract_surface,
                         cairo_rectangle_int_t  *rectangle)
{
    cairo_beos_surface_t *surface = reinterpret_cast<cairo_beos_surface_t*>(
                                          abstract_surface);
    AutoLockView locker(surface->view);
    if (!locker)
      return FALSE;

    *rectangle = _brect_to_cairo_rectangle (surface->view->Bounds());
    return TRUE;
}

static const struct _cairo_surface_backend cairo_beos_surface_backend = {
    CAIRO_SURFACE_TYPE_BEOS,
    _cairo_beos_surface_create_similar,
    _cairo_beos_surface_finish,
    _cairo_beos_surface_acquire_source_image,
    _cairo_beos_surface_release_source_image,
    _cairo_beos_surface_acquire_dest_image,
    _cairo_beos_surface_release_dest_image,
    NULL, /* clone_similar */
    _cairo_beos_surface_composite, /* composite */
    _cairo_beos_surface_fill_rectangles,
    NULL, /* composite_trapezoids */
    NULL, /* create_span_renderer */
    NULL, /* check_span_renderer */
    NULL, /* copy_page */
    NULL, /* show_page */
    _cairo_beos_surface_get_extents,
    NULL,  /* old_show_glyphs */
    NULL, /* get_font_options */
    NULL, /* flush */
    NULL, /* mark_dirty_rectangle */
    NULL, /* scaled_font_fini */
    NULL, /* scaled_glyph_fini */

    NULL, /* paint */
    NULL, /* mask */
    NULL, /* stroke */
    NULL, /* fill */
    NULL  /* show_glyphs */
};

static cairo_surface_t *
_cairo_beos_surface_create_internal (BView*   view,
                             BBitmap* bmp,
                             bool     owns_bitmap_view)
{
    // Must use malloc, because cairo code will use free() on the surface
    cairo_beos_surface_t *surface = static_cast<cairo_beos_surface_t*>(
                              malloc(sizeof(cairo_beos_surface_t)));
    if (surface == NULL) {
      _cairo_error (CAIRO_STATUS_NO_MEMORY);
        return const_cast<cairo_surface_t*>(&_cairo_surface_nil);
    }

    cairo_content_t content = CAIRO_CONTENT_COLOR;
    if (bmp && (bmp->ColorSpace() == B_RGBA32 || bmp->ColorSpace() == B_RGBA15))
      content = CAIRO_CONTENT_COLOR_ALPHA;
    _cairo_surface_init (&surface->base,
                   &cairo_beos_surface_backend,
                   NULL, /* device */
                   content);

    surface->view = view;
    surface->bitmap = bmp;
    surface->owns_bitmap_view = owns_bitmap_view;

    surface->clip_region = NULL;

    return &surface->base;
}

/**
 * cairo_beos_surface_create:
 * @view: The view to draw on
 *
 * Creates a Cairo surface that draws onto a BeOS BView.
 * The caller must ensure that the view does not get deleted before the surface.
 * If the view is attached to a bitmap rather than an on-screen window, use
 * cairo_beos_surface_create_for_bitmap() instead of this function.
 **/
cairo_surface_t *
cairo_beos_surface_create (BView* view)
{
    return cairo_beos_surface_create_for_bitmap(view, NULL);
}

/**
 * cairo_beos_surface_create_for_bitmap:
 * @view: The view to draw on
 * @bmp: The bitmap to which the view is attached
 *
 * Creates a Cairo surface that draws onto a BeOS BView which is attached to a
 * BBitmap.
 * The caller must ensure that the view and the bitmap do not get deleted
 * before the surface.
 *
 * For views that draw to a bitmap (as opposed to a screen), use this function
 * rather than cairo_beos_surface_create(). Not using this function WILL lead to
 * incorrect behaviour.
 *
 * For now, only views that draw to the entire area of bmp are supported.
 * The view must already be attached to the bitmap.
 **/
cairo_surface_t *
cairo_beos_surface_create_for_bitmap (BView*   view,
                              BBitmap* bmp)
{
    return _cairo_beos_surface_create_internal(view, bmp);
}

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