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multithreading for pdf rendering (initial, zoom). close #2433
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@j-dimension
j-dimension committed May 6, 2024
1 parent 53f5c8c commit 5e9f359
Showing 1 changed file with 141 additions and 66 deletions.
207 changes: 141 additions & 66 deletions ...nt/src/com/jdimension/jlawyer/client/editors/documents/viewer/PdfImageScrollingPanel.java
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Expand Up @@ -669,13 +669,13 @@
import java.awt.Image;
import java.awt.Point;
import java.awt.event.AdjustmentEvent;
import java.awt.event.AdjustmentListener;
import java.awt.image.BufferedImage;
import java.io.ByteArrayInputStream;
import java.util.HashMap;
import javax.swing.ImageIcon;
import javax.swing.JLabel;
import javax.swing.SwingConstants;
import javax.swing.SwingUtilities;
import javax.swing.border.EmptyBorder;
import org.apache.log4j.Logger;
import org.apache.pdfbox.pdmodel.PDDocument;
Expand All @@ -690,6 +690,7 @@ public class PdfImageScrollingPanel extends javax.swing.JPanel implements Previe

private static final Logger log = Logger.getLogger(PdfImageScrollingPanel.class.getName());
private static final int MAX_RENDER_PAGES = 20;
private Object zoomSemaphore = "";

HashMap<Integer, BufferedImage> orgImage = new HashMap<>();

Expand All @@ -701,6 +702,7 @@ public class PdfImageScrollingPanel extends javax.swing.JPanel implements Previe
private String documentId = null;

private int zoomFactor = 100;
private int lastZoomFactorRequest=-1;

/**
* Creates new form PlaintextPanel
Expand All @@ -718,13 +720,13 @@ public PdfImageScrollingPanel(String fileName, byte[] content) {

this.jScrollPane1.getVerticalScrollBar().addAdjustmentListener((AdjustmentEvent e) -> {
// Assuming scrollPane is your JScrollPane instance

int viewPosition = jScrollPane1.getViewport().getViewPosition().y;

int totalHeight = 0;
Component[] components = pnlPages.getComponents();
int labelIndex = -1;

// Calculate the index of the JLabel currently displayed
for (int i = 0; i < components.length; i++) {
totalHeight += components[i].getHeight();
Expand All @@ -733,20 +735,20 @@ public PdfImageScrollingPanel(String fileName, byte[] content) {
break;
}
}

// Now you have the index of the JLabel currently displayed
// You can access it like this:
if (labelIndex != -1 && labelIndex < components.length) {
//JLabel currentLabel = (JLabel) components[labelIndex];
// Do whatever you need with the currentLabel
lblCurrentPage.setText("" + (labelIndex+1) + "/" + renderedPages);

lblCurrentPage.setText("" + (labelIndex + 1) + "/" + renderedPages);
currentPage = labelIndex;
cmdFirstPage.setEnabled(currentPage > 0);
cmdPageBackward.setEnabled(currentPage > 0);
cmdLastPage.setEnabled((currentPage+1) < renderedPages);
cmdPageForward.setEnabled((currentPage+1) < renderedPages);
cmdLastPage.setEnabled((currentPage + 1) < renderedPages);
cmdPageForward.setEnabled((currentPage + 1) < renderedPages);

}
});

Expand Down Expand Up @@ -903,15 +905,15 @@ private void scrollToPage(int page) {

// Calculate the index of the JLabel currently displayed
for (int i = 0; i < components.length; i++) {

if (i == page) {
this.currentPage = page;
this.jScrollPane1.getViewport().setViewPosition(new Point(0, totalHeight));
this.lblCurrentPage.setText("" + (page + 1) + "/" + this.renderedPages);
cmdFirstPage.setEnabled(currentPage > 0);
cmdPageBackward.setEnabled(currentPage > 0);
cmdLastPage.setEnabled((currentPage+1) < renderedPages);
cmdPageForward.setEnabled((currentPage+1) < renderedPages);
cmdLastPage.setEnabled((currentPage + 1) < renderedPages);
cmdPageForward.setEnabled((currentPage + 1) < renderedPages);

break;
}
Expand All @@ -933,38 +935,67 @@ private void cmdFirstPageActionPerformed(java.awt.event.ActionEvent evt) {//GEN-
}//GEN-LAST:event_cmdFirstPageActionPerformed

private void cmdLastPageActionPerformed(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_cmdLastPageActionPerformed
this.scrollToPage(this.renderedPages-1);
this.scrollToPage(this.renderedPages - 1);
}//GEN-LAST:event_cmdLastPageActionPerformed

private void sliderZoomStateChanged(javax.swing.event.ChangeEvent evt) {//GEN-FIRST:event_sliderZoomStateChanged
this.zoomFactor = this.sliderZoom.getValue();
ClientSettings.getInstance().setConfiguration("pdf.zoomfactor", "" + this.zoomFactor);
// this.showPage(this.content, this.currentPage, this.zoomFactor);
if(this.sliderZoom.getValue()==this.lastZoomFactorRequest) {
return;
}
this.lastZoomFactorRequest=this.sliderZoom.getValue();

this.pnlPages.removeAll();
new Thread(() -> {

int i = 0;
while (this.orgImage.containsKey(i)) {
// need to subtract the height of the page navigation buttons, but
// the panel has not been layed out yet, so there is no height we could query
int height = Math.max(this.getHeight() - 55, 400);
this.zoomFactor = this.sliderZoom.getValue();
int threadZoomFactor = this.sliderZoom.getValue();
ClientSettings.getInstance().setConfiguration("pdf.zoomfactor", "" + this.zoomFactor);

float scaleFactor = (float) height / (float) this.orgImage.get(i).getHeight();
int width = (int) ((float) this.orgImage.get(i).getWidth() * scaleFactor);
try {
synchronized (zoomSemaphore) {
if (threadZoomFactor != sliderZoom.getValue()) {
return;
}
}

height = (int) ((float) height * ((float) ((float) zoomFactor / 100f)));
width = (int) ((float) width * ((float) ((float) zoomFactor / 100f)));
SwingUtilities.invokeAndWait(() -> {
this.pnlPages.removeAll();
});

Image bi2 = this.orgImage.get(i).getScaledInstance(width, height, Image.SCALE_SMOOTH);
int i = 0;
while (this.orgImage.containsKey(i)) {
// need to subtract the height of the page navigation buttons, but
// the panel has not been layed out yet, so there is no height we could query
int height = Math.max(this.getHeight() - 55, 400);

JLabel lblPage = new JLabel();
lblPage.setBorder(new EmptyBorder(0, 0, 10, 0));
lblPage.setHorizontalAlignment(SwingConstants.CENTER);
this.pnlPages.add(lblPage);
float scaleFactor = (float) height / (float) this.orgImage.get(i).getHeight();
int width = (int) ((float) this.orgImage.get(i).getWidth() * scaleFactor);

ThreadUtils.updateLabelIcon(lblPage, new ImageIcon(bi2), "");
i++;
}
height = (int) ((float) height * ((float) ((float) zoomFactor / 100f)));
width = (int) ((float) width * ((float) ((float) zoomFactor / 100f)));

Image bi2 = this.orgImage.get(i).getScaledInstance(width, height, Image.SCALE_SMOOTH);

SwingUtilities.invokeAndWait(() -> {

synchronized (zoomSemaphore) {
if (threadZoomFactor != sliderZoom.getValue()) {
return;
}
JLabel lblPage = new JLabel();
lblPage.setBorder(new EmptyBorder(0, 0, 10, 0));
lblPage.setHorizontalAlignment(SwingConstants.CENTER);
this.pnlPages.add(lblPage);

lblPage.setIcon(new ImageIcon(bi2));
lblPage.setText("");
}
});
i++;
}
} catch (Throwable t) {
log.error(t);
}
}).start();

}//GEN-LAST:event_sliderZoomStateChanged

Expand Down Expand Up @@ -994,6 +1025,8 @@ public void showStatus(String text) {
}

private void renderContent(byte[] content, int zoomFactor) {
this.sliderZoom.setEnabled(false);
this.cmdFitToScreen.setEnabled(false);
this.content = content;
try {
if (content != null) {
Expand All @@ -1003,6 +1036,8 @@ private void renderContent(byte[] content, int zoomFactor) {
} else {
log.info("PDF to render has no byte content (null)");
this.showStatus("Daten für die Vorschaudarstellung sind ungültig.");
this.sliderZoom.setEnabled(true);
this.cmdFitToScreen.setEnabled(true);
return;
}

Expand All @@ -1013,49 +1048,89 @@ private void renderContent(byte[] content, int zoomFactor) {

this.lblTotalPages.setText("" + inputPDF.getNumberOfPages());


this.cmdFirstPage.setEnabled(false);
this.cmdPageBackward.setEnabled(false);
this.cmdLastPage.setEnabled(inputPDF.getNumberOfPages() > 1);
this.cmdPageForward.setEnabled(inputPDF.getNumberOfPages() > 1);

this.pnlPages.removeAll();

for (int i = 0; i < Math.min(inputPDF.getNumberOfPages(), MAX_RENDER_PAGES); i++) {
BufferedImage buffImg = pdfRenderer.renderImageWithDPI(i, 300, ImageType.RGB);
this.orgImage.put(i, buffImg);

// need to subtract the height of the page navigation buttons, but
// the panel has not been layed out yet, so there is no height we could query
int height = Math.max(this.getHeight() - 55, 400);

float scaleFactor = (float) height / (float) this.orgImage.get(i).getHeight();
int width = (int) ((float) this.orgImage.get(i).getWidth() * scaleFactor);

height = (int) ((float) height * ((float) ((float) zoomFactor / 100f)));
width = (int) ((float) width * ((float) ((float) zoomFactor / 100f)));

Image bi2 = this.orgImage.get(i).getScaledInstance(width, height, Image.SCALE_SMOOTH);

JLabel lblPage = new JLabel();
lblPage.setBorder(new EmptyBorder(0, 0, 10, 0));
lblPage.setHorizontalAlignment(SwingConstants.CENTER);
this.pnlPages.add(lblPage);

ThreadUtils.updateLabelIcon(lblPage, new ImageIcon(bi2), "");

this.renderedPages = i + 1;

}
this.lblCurrentPage.setText("1" + "/" + this.renderedPages);

inputPDF.close();

new Thread(() -> {
for (int i = 0; i < Math.min(inputPDF.getNumberOfPages(), MAX_RENDER_PAGES); i++) {
try {
BufferedImage buffImg = pdfRenderer.renderImageWithDPI(i, 200, ImageType.RGB);
orgImage.put(i, buffImg);
// need to subtract the height of the page navigation buttons, but
// the panel has not been layed out yet, so there is no height we could query
int height1 = Math.max(getHeight() - 55, 400);
float scaleFactor = (float) height1 / (float) orgImage.get(i).getHeight();
int width1 = (int) ((float) orgImage.get(i).getWidth() * scaleFactor);
height1 = (int) ((float) height1 * ((float) ((float) zoomFactor / 100f)));
width1 = (int) ((float) width1 * ((float) ((float) zoomFactor / 100f)));
Image bi2 = orgImage.get(i).getScaledInstance(width1, height1, Image.SCALE_SMOOTH);

SwingUtilities.invokeAndWait(() -> {
JLabel lblPage = new JLabel();
lblPage.setBorder(new EmptyBorder(0, 0, 10, 0));
lblPage.setHorizontalAlignment(SwingConstants.CENTER);
pnlPages.add(lblPage);
lblPage.setIcon(new ImageIcon(bi2));
lblPage.setText("");
});

renderedPages = i + 1;
} catch (Throwable t) {
log.error(t);
this.sliderZoom.setEnabled(true);
this.cmdFitToScreen.setEnabled(true);
}
}
try {
this.sliderZoom.setEnabled(true);
this.cmdFitToScreen.setEnabled(true);
lblCurrentPage.setText("1" + "/" + renderedPages);
inputPDF.close();
} catch (Throwable t) {
log.error(t);
}
}).start();

// for (int i = 0; i < Math.min(inputPDF.getNumberOfPages(), MAX_RENDER_PAGES); i++) {
// BufferedImage buffImg = pdfRenderer.renderImageWithDPI(i, 200, ImageType.RGB);
// this.orgImage.put(i, buffImg);
//
// // need to subtract the height of the page navigation buttons, but
// // the panel has not been layed out yet, so there is no height we could query
// int height = Math.max(this.getHeight() - 55, 400);
//
// float scaleFactor = (float) height / (float) this.orgImage.get(i).getHeight();
// int width = (int) ((float) this.orgImage.get(i).getWidth() * scaleFactor);
//
// height = (int) ((float) height * ((float) ((float) zoomFactor / 100f)));
// width = (int) ((float) width * ((float) ((float) zoomFactor / 100f)));
//
// Image bi2 = this.orgImage.get(i).getScaledInstance(width, height, Image.SCALE_SMOOTH);
//
// JLabel lblPage = new JLabel();
// lblPage.setBorder(new EmptyBorder(0, 0, 10, 0));
// lblPage.setHorizontalAlignment(SwingConstants.CENTER);
// this.pnlPages.add(lblPage);
//
// ThreadUtils.updateLabelIcon(lblPage, new ImageIcon(bi2), "");
//
// this.renderedPages = i + 1;
//
// }
// this.lblCurrentPage.setText("1" + "/" + this.renderedPages);
//
// inputPDF.close();
}

} catch (Throwable t) {
log.error("error rendering PDF preview for " + this.fileName, t);
showStatus("Vorschau nicht verfügbar");
this.sliderZoom.setEnabled(true);
this.cmdFitToScreen.setEnabled(true);
}
}

Expand Down

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