From 2daf1a6d53832d3b5937d7d813332a1c3bb53ecc Mon Sep 17 00:00:00 2001
From: Jakub Melka <Mgr.Jakub.Melka@gmail.com>
Date: Sun, 16 Jul 2023 18:56:50 +0200
Subject: [PATCH] Issue #59: Set physical dimensions of images in the
 rasterizer

---
 Pdf4QtLib/sources/pdfrenderer.cpp | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/Pdf4QtLib/sources/pdfrenderer.cpp b/Pdf4QtLib/sources/pdfrenderer.cpp
index f22bc02..ecef9ad 100644
--- a/Pdf4QtLib/sources/pdfrenderer.cpp
+++ b/Pdf4QtLib/sources/pdfrenderer.cpp
@@ -317,6 +317,14 @@ QImage PDFRasterizer::render(PDFInteger pageIndex,
         image.convertTo(QImage::Format_ARGB32_Premultiplied);
     }
 
+    // Calculate image DPI
+    QSizeF rotatedSizeInMeters = page->getRotatedMediaBoxMM().size() / 1000.0;
+    QSizeF rotatedSizeInPixels = image.size();
+    qreal dpiX = rotatedSizeInPixels.width() / rotatedSizeInMeters.width();
+    qreal dpiY = rotatedSizeInPixels.height() / rotatedSizeInMeters.height();
+    image.setDotsPerMeterX(qCeil(dpiX));
+    image.setDotsPerMeterY(qCeil(dpiY));
+
     return image;
 }