gvdevice_gdiplus.cpp

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/*************************************************************************
 * Copyright (c) 2011 AT&T Intellectual Property
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors: Details at https://graphviz.org
 *************************************************************************/
 
#include "config.h"
 
 
#include <gvc/gvplugin_device.h>
#include <gvc/gvplugin_render.h>
#include <gvc/gvio.h>
#include "gvplugin_gdiplus.h"
 
using namespace Gdiplus;
 
static void gdiplus_format(GVJ_t *job)
{
        UseGdiplus();
 
        /* allocate memory and attach stream to it */
        HGLOBAL buffer = GlobalAlloc(GMEM_MOVEABLE, 0);
        IStream *stream = nullptr;
        CreateStreamOnHGlobal(buffer, FALSE, &stream);  /* FALSE means don't deallocate buffer when releasing stream */
 
        Bitmap bitmap(
                job->width,                                             /* width in pixels */
                job->height,                                    /* height in pixels */
                job->width * BYTES_PER_PIXEL,   /* bytes per row: exactly width # of pixels */
                PixelFormat32bppPARGB,                  /* pixel format: corresponds to CAIRO_FORMAT_ARGB32 */
                job->imagedata);                                /* pixel data from job */
        SaveBitmapToStream(bitmap, stream, job->device.id);
 
        /* blast the streamed buffer back to the gvdevice */
        /* NOTE: this is somewhat inefficient since we should be streaming directly to gvdevice rather than buffering first */
        /* ... however, GDI+ requires any such direct IStream to implement Seek Read, Write, Stat methods and gvdevice really only offers a write-once model */
        stream->Release();
        gvwrite(job, (const char*)GlobalLock(buffer), GlobalSize(buffer));
 
        GlobalFree(buffer);
}
 
static gvdevice_engine_t gdiplus_engine = {
    nullptr,            /* gdiplus_initialize */
    gdiplus_format,
    nullptr,            /* gdiplus_finalize */
};
 
static gvdevice_features_t device_features_gdiplus = {
        GVDEVICE_BINARY_FORMAT
          | GVDEVICE_DOES_TRUECOLOR,/* flags */
        {0.,0.},                    /* default margin - points */
        {0.,0.},                    /* default page width, height - points */
        {96.,96.},                  /* dpi */
};
 
gvplugin_installed_t gvdevice_gdiplus_types_for_cairo[] = {
        {FORMAT_BMP, "bmp:cairo", 8, &gdiplus_engine, &device_features_gdiplus},
        {FORMAT_GIF, "gif:cairo", 8, &gdiplus_engine, &device_features_gdiplus},
        {FORMAT_JPEG, "jpe:cairo", 8, &gdiplus_engine, &device_features_gdiplus},
        {FORMAT_JPEG, "jpeg:cairo", 8, &gdiplus_engine, &device_features_gdiplus},
        {FORMAT_JPEG, "jpg:cairo", 8, &gdiplus_engine, &device_features_gdiplus},
        {FORMAT_PNG, "png:cairo", 8, &gdiplus_engine, &device_features_gdiplus},
        {FORMAT_TIFF, "tif:cairo", 8, &gdiplus_engine, &device_features_gdiplus},
        {FORMAT_TIFF, "tiff:cairo", 8, &gdiplus_engine, &device_features_gdiplus},
        {0, nullptr, 0, nullptr, nullptr}
};