org.jpedal.utils.PdfPrintTransform Maven / Gradle / Ivy
/*
* ===========================================
* Java Pdf Extraction Decoding Access Library
* ===========================================
*
* Project Info: http://www.idrsolutions.com
* Help section for developers at http://www.idrsolutions.com/support/
*
* (C) Copyright 1997-2015 IDRsolutions and Contributors.
*
* This file is part of JPedal/JPDF2HTML5
*
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* ---------------
* PdfPrintTransform.java
* ---------------
*/
package org.jpedal.utils;
/**
* Encapsulates the creation of a AffineTransform that mimics the effects
* of the printing options available in Adobe Acrobat.
*
* The available options additional are auto rotate and centre, fit to page and shrink to page.
* If page is larger than the page when asked to fit or smaller than the page when asked to shrink
* it is unaffected apart from being centred. This is same effect found in Acrobat printing.
*
Currently implements Printable for testing purposes
*
*/
import java.awt.Rectangle;
import java.awt.geom.AffineTransform;
import java.awt.print.PageFormat;
import org.jpedal.objects.PrinterOptions;
public class PdfPrintTransform
{
private boolean autoRotate;
private final boolean chooseSourceByPDFSize;
private int scalingMode;
private double scalingFactor;
private boolean centerOnScaling;
private Rectangle crop;
private PageFormat format;
/**
* Create instance with given modes of orientation.
*
* @param autoRotate specifies if we should rotate the page to better fit the output page
* @param centerOnScaling specifies if we should centre the print output on the page
* @param scalingMode the scaling mode to use as specified in PrinterOptions
* @param chooseSourceByPDFSize specifies if we use the PDF page size to determines print page size
*/
public PdfPrintTransform(final boolean autoRotate, final boolean centerOnScaling, final int scalingMode, final boolean chooseSourceByPDFSize){
this.autoRotate = autoRotate;
this.centerOnScaling=centerOnScaling;
this.chooseSourceByPDFSize = chooseSourceByPDFSize;
setPageScaling(scalingMode);
scalingFactor = 1;
}
/**
* Create a AffineTransform to effect page according to scaling and centring options.
*
* @param width crop box width
* @param height crop box height
* @param pageFormat describing dimensions of target printer page
* @return transformation required to render PDF page to printer page
*/
public AffineTransform getPageTransform(final int cropBoxX, final int cropBoxY, final int width, final int height, final int pageRotation, final PageFormat pageFormat){
return getPageTransform(new Rectangle(cropBoxX, cropBoxY, width, height), pageRotation, pageFormat);
}
/**
* @param b true to automatically rotate and centre page
*/
@SuppressWarnings("UnusedDeclaration")
public void setAutoRotateAndCenter(final boolean b){
autoRotate = b;
centerOnScaling = b;
}
/**
* @param rotate true to automatically rotate page
* @param center true to automatically centre page
*/
@SuppressWarnings("UnusedDeclaration")
public void setAutoRotateAndCenter(final boolean rotate, final boolean center){
autoRotate = rotate;
centerOnScaling = center;
}
/**
* Set the desired page scaling mode. The permitted settings are as follows:
* PrinterOptions.PAGE_SCALING_NONE PrinterOptions.PAGE_SCALING_FIT_TO_PRINTER_MARGINS
* PrinterOptions.PAGE_SCALING_REDUCE_TO_PRINTER_MARGINS.
*
* @param scalingMode the desired scale of the printed page
*/
public void setPageScaling(final int scalingMode){
switch (scalingMode) {
case PrinterOptions.PAGE_SCALING_NONE:
case PrinterOptions.PAGE_SCALING_FIT_TO_PRINTER_MARGINS:
case PrinterOptions.PAGE_SCALING_REDUCE_TO_PRINTER_MARGINS:
this.scalingMode = scalingMode;
break;
default:
throw new IllegalArgumentException("Unknown Scaling mode type: " + scalingMode);
}
}
/**
* Create a AffineTransform to effect page according to scaling and
* centring options.
*
* @param cropBox
* @param pageRotation
* @param pageFormat
* @return
*/
public AffineTransform getPageTransform(final Rectangle cropBox, int pageRotation, final PageFormat pageFormat){
crop = cropBox;
format = pageFormat;
final AffineTransform result = new AffineTransform();
scalingFactor = 1; //Reset scaling factor
boolean shouldRotate = false;
//Find whether the page needs to be rotated for best fit
if(autoRotate || chooseSourceByPDFSize) {
final boolean isPageWidthLong = pageFormat.getImageableWidth() > pageFormat.getImageableHeight();
boolean isImageWidthLong = crop.width > crop.height;
//As adobe does we print page based on the rotation the page is displayed at
//so take this into account when determining if the width is longer than height
if(pageRotation==90 || pageRotation==270){
//Use height as width
isImageWidthLong = crop.width < crop.height;
}
shouldRotate = isPageWidthLong != isImageWidthLong;
}
//Printed page will output all upside down to factor this out we add 180 on to all page rotations
if(!shouldRotate){
pageRotation += 180;
if(pageRotation>360) {
pageRotation-=360;
}
}else{
//To rotate to match adobe requires a 270 degree turn on top of the 180 to turn page upright.
//Instead of adding 270 we ignore the 180 rotation and instead only rotate by 90 (as total is 90 over a full 360 spin).
pageRotation += 90;
if(pageRotation>360) {
pageRotation-=360;
}
}
//Calculate scaling factor
final double w = pageRotation%180==0 ? crop.width : crop.height;
final double h = pageRotation%180==0 ? crop.height : crop.width;
final double widthRatio = (pageFormat.getImageableWidth() - 1) / w;
final double heightRatio = (pageFormat.getImageableHeight() - 1) / h;
if(((widthRatio < 1 || heightRatio < 1) && scalingMode == PrinterOptions.PAGE_SCALING_REDUCE_TO_PRINTER_MARGINS) ||
(scalingMode == PrinterOptions.PAGE_SCALING_FIT_TO_PRINTER_MARGINS)) {
scalingFactor = widthRatio < heightRatio ? widthRatio : heightRatio;
}
//If page is had rotation, rotate content for printing.
if(pageRotation!=0 || shouldRotate){
//Apply rotation to transform
applyRotation(result, pageRotation);
}
//Factor out crop box
if(crop.x!=0 || crop.y!=0){
applyCrop(result, pageRotation);
}
//Offset based on imagable area
applyOffset(result, pageRotation);
//if we center the page, center it here
if(centerOnScaling){
applyCentering(result, pageRotation);
}
//Scale page
if(scalingMode != PrinterOptions.PAGE_SCALING_NONE) {
result.scale(scalingFactor, scalingFactor);
}
//Flip page
result.scale(-1, 1);
result.translate(-crop.width, 0);
//Ensure these values are null by the end of this method
crop = null;
format = null;
//Return transform for the page.
return result;
}
//Add the rotation of the page to the transform so page can appear in the imageable area
private void applyRotation(final AffineTransform result, final int rotation){
final int factor = rotation / 90;
//Perform rotation
result.rotate(factor * Math.PI / 2.0);
//Move page back into display, this varies based on rotation
switch(factor){
case 1 : // 90 degree rotation
result.translate(0, -(crop.height*scalingFactor));
break;
case 2 : //180 degree rotation
result.translate(-(crop.width*scalingFactor), -(crop.height*scalingFactor));
break;
case 3 : //270 degree rotation
result.translate(-(crop.width*scalingFactor), 0);
break;
}
}
//Add the crop of the page to the transform so page can appear in the imageable area
private void applyCrop(final AffineTransform result, final int rotation){
/**
* Annoyingly I do not understand why the code below works.
* By my reckoning the crop x / y values should change from positive to negative based on rotation.
* How ever when I tried this the crop values were broke in all cases except 90 degrees.
* When I tested this combination in other broken cases, they worked correctly..
*
* I have kept the switch in here in case I am proved wrong at any point so we can quickly tweak
* the values for different rotations.
*/
switch(rotation){
case 0 :
result.translate(crop.x*scalingFactor, -crop.y*scalingFactor);
break;
case 90 :
result.translate(crop.x*scalingFactor, -crop.y*scalingFactor);
break;
case 180 :
result.translate(crop.x*scalingFactor, -crop.y*scalingFactor);
break;
case 270 :
result.translate(crop.x*scalingFactor, -crop.y*scalingFactor);
break;
}
}
//Add the offset of the imageable area
private void applyOffset(final AffineTransform result, final int rotation){
switch(rotation){
case 0 :
result.translate(format.getImageableX(), format.getImageableY());
break;
case 90 :
result.translate(format.getImageableX(), -format.getImageableY());
break;
case 180 :
result.translate(-format.getImageableX(), -format.getImageableY());
break;
case 270 :
result.translate(-format.getImageableX(), format.getImageableY());
break;
}
}
//Add an offset so page will be centered in the iamgeable area
private void applyCentering(final AffineTransform result, final int rotation){
double centerOnX = 0;
double centerOnY = 0;
switch (rotation) {
case 0:
centerOnX = (format.getImageableWidth()-(crop.width*scalingFactor))/2;
centerOnY = (format.getImageableHeight()-(crop.height*scalingFactor))/2;
break;
case 90:
centerOnX = (format.getImageableHeight()-(crop.width*scalingFactor))/2;
centerOnY = -((format.getImageableWidth()-(crop.height*scalingFactor))/2);
break;
case 180:
centerOnX = -(format.getImageableWidth()-(crop.width*scalingFactor))/2;
centerOnY = -(format.getImageableHeight()-(crop.height*scalingFactor))/2;
break;
case 270:
centerOnX = -(format.getImageableHeight()-(crop.width*scalingFactor))/2;
centerOnY = (format.getImageableWidth()-(crop.height*scalingFactor))/2;
break;
}
result.translate(centerOnX, centerOnY);
}
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