src/avenprcore.cc

   1 /* avenprcore.cc
   2  * Printer independent parts of Survex printer drivers
   3  * Copyright (C) 1993-2002,2004,2005,2006,2010,2011,2012,2013,2014,2015,2016 Olly Betts
   4  * Copyright (C) 2004 Philip Underwood
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  19  */
  20
  21 #include <config.h>
  22
  23 #include <algorithm>
  24 #include <math.h>
  25
  26 #include "useful.h"
  27 #include "avenprcore.h"
  28
  29 #if defined __WXMSW__ || defined __WXMAC__
  30 # include <wx/dcprint.h>
  31 #else
  32 # include <wx/dcps.h>
  33 #endif
  34 #include <wx/print.h>
  35
  36 layout::layout(wxPageSetupDialogData* data)
  37 {
  38     if (data) {
  39         // Printing.
  40
  41         // Create a temporary wxPrinterDC/wxPostScriptDC so we can get access
  42         // to the size of the printable area in mm to allow us to calculate how
  43         // many pages will be needed.
  44         //
  45         // It may seem like data->GetPaperSize() would tell us this page size
  46         // without having to construct a temporary DC, but that just returns
  47         // (0, 0) for the size, at least with wxGTK 3.0.2.
  48 #if defined __WXMSW__ || defined __WXMAC__
  49         wxPrinterDC pdc(data->GetPrintData());
  50 #else
  51         wxPostScriptDC pdc(data->GetPrintData());
  52 #endif
  53         // Calculate the size of the printable area in mm to allow us to work
  54         // out how many pages will be needed for a given scale.
  55         wxSize size = pdc.GetSizeMM();
  56         size.DecBy(data->GetMarginBottomRight());
  57         size.DecBy(data->GetMarginTopLeft());
  58         PaperWidth = size.x;
  59         // Allow for our footer.
  60         PaperDepth = size.y - FOOTER_HEIGHT_MM;
  61     } else {
  62         // Exporting.
  63         PaperWidth = PaperDepth = 0;
  64     }
  65 }
  66
  67 void
  68 layout::pages_required() {
  69     double image_dx, image_dy;
  70     double image_centre_x, image_centre_y;
  71     double paper_centre_x, paper_centre_y;
  72
  73     double allow = 21.0;
  74     if (Legend) allow += 30.0;
  75     double Sc = 1000 / Scale;
  76     image_dx = (xMax - xMin) * Sc;
  77     if (PaperWidth > 0.0) {
  78         pagesX = (int)ceil((image_dx + 19.0) / PaperWidth);
  79     } else {
  80         /* paperwidth not fixed (eg window or roll printer/plotter) */
  81         pagesX = 1;
  82         PaperWidth = image_dx + 19.0;
  83     }
  84     paper_centre_x = (pagesX * PaperWidth) / 2;
  85     image_centre_x = Sc * (xMax + xMin) / 2;
  86     xOrg = paper_centre_x - image_centre_x;
  87
  88     image_dy = (yMax - yMin) * Sc;
  89     if (PaperDepth > 0.0) {
  90         pagesY = (int)ceil((image_dy + allow) / PaperDepth);
  91     } else {
  92         /* paperdepth not fixed (eg window or roll printer/plotter) */
  93         pagesY = 1;
  94         PaperDepth = image_dy + allow;
  95     }
  96     paper_centre_y = 20 + (pagesY * PaperDepth) / 2;
  97     image_centre_y = Sc * (yMax + yMin) / 2;
  98     yOrg = paper_centre_y - image_centre_y;
  99
 100     pages = pagesX * pagesY;
 101 }
 102
 103 #define DEF_RATIO (1.0/(double)DEFAULT_SCALE)
 104
 105 /* pick a scale which will make it fit in the desired size */
 106 void
 107 layout::pick_scale(int x, int y)
 108 {
 109    pagesX = x;
 110    pagesY = y;
 111    pages = x * y;
 112
 113    double Sc_x, Sc_y;
 114    /*    pagesY = ceil((image_dy+allow)/PaperDepth)
 115     * so (image_dy+allow)/PaperDepth <= pagesY < (image_dy+allow)/PaperDepth+1
 116     * so image_dy <= pagesY*PaperDepth-allow < image_dy+PaperDepth
 117     * and Sc = image_dy / (yMax-yMin)
 118     * so Sc <= (pagesY*PaperDepth-allow)/(yMax-yMin) < Sc+PaperDepth/(yMax-yMin)
 119     */
 120    Sc_x = Sc_y = DEF_RATIO;
 121    if (PaperWidth > 0.0 && xMax > xMin)
 122       Sc_x = (x * PaperWidth - 19.0) / (xMax - xMin);
 123    if (PaperDepth > 0.0 && yMax > yMin) {
 124       double allow = 21.0;
 125       if (Legend) allow += 30.0;
 126       Sc_y = (y * PaperDepth - allow) / (yMax - yMin);
 127    }
 128
 129    Sc_x = std::min(Sc_x, Sc_y) * 0.99; /* shrink by 1% so we don't cock up */
 130 #if 0 /* this picks a nice (in some sense) ratio, but is too stingy */
 131    double E = pow(10.0, floor(log10(Sc_x)));
 132    Sc_x = floor(Sc_x / E) * E;
 133 #endif
 134
 135    double Scale_exact = 1000.0 / Sc_x;
 136
 137    /* trim to 2 s.f. (rounding up) */
 138    double w = pow(10.0, floor(log10(Scale_exact) - 1.0));
 139    Scale = ceil(Scale_exact / w) * w;
 140 }