From 5cf53e39d0b3809a453bb7316a8ebc66eae746a0 Mon Sep 17 00:00:00 2001
From: Renan <82916964+thisisrenan@users.noreply.github.com>
Date: Wed, 13 Nov 2024 08:12:30 -0300
Subject: [PATCH] Increase watermark coverage to fill page (#2049) (#2220)

* Increase watermark coverage to fill page (#2049)

* Increase watermark coverage to fill page with the new calculation (#2049)
---
 .../api/security/WatermarkController.java     | 26 ++++++++++++++-----
 1 file changed, 20 insertions(+), 6 deletions(-)

diff --git a/src/main/java/stirling/software/SPDF/controller/api/security/WatermarkController.java b/src/main/java/stirling/software/SPDF/controller/api/security/WatermarkController.java
index de7efd71..7bf9bbb7 100644
--- a/src/main/java/stirling/software/SPDF/controller/api/security/WatermarkController.java
+++ b/src/main/java/stirling/software/SPDF/controller/api/security/WatermarkController.java
@@ -187,18 +187,32 @@ public class WatermarkController {
         float watermarkHeight = heightSpacer + fontSize * textLines.length;
         float pageWidth = page.getMediaBox().getWidth();
         float pageHeight = page.getMediaBox().getHeight();
-        int watermarkRows = (int) (pageHeight / watermarkHeight + 1);
-        int watermarkCols = (int) (pageWidth / watermarkWidth + 1);
+
+
+        //Calculating the new width and height depending on the angle.
+        float radians = (float) Math.toRadians(rotation);
+        float newWatermarkWidth =
+                (float)
+                        (Math.abs(watermarkWidth * Math.cos(radians))
+                                + Math.abs(watermarkHeight * Math.sin(radians)));
+        float newWatermarkHeight =
+                (float)
+                        (Math.abs(watermarkWidth * Math.sin(radians))
+                                + Math.abs(watermarkHeight * Math.cos(radians)));
+
+        //Calculating the number of rows and columns.
+        int watermarkRows = (int) (pageHeight / newWatermarkHeight + 1);
+        int watermarkCols = (int) (pageWidth / newWatermarkWidth + 1);
 
         // Add the text watermark
-        for (int i = 0; i < watermarkRows; i++) {
-            for (int j = 0; j < watermarkCols; j++) {
+        for (int i = 0; i <= watermarkRows; i++) {
+            for (int j = 0; j <= watermarkCols; j++) {
                 contentStream.beginText();
                 contentStream.setTextMatrix(
                         Matrix.getRotateInstance(
                                 (float) Math.toRadians(rotation),
-                                j * watermarkWidth,
-                                i * watermarkHeight));
+                                j * newWatermarkWidth,
+                                i * newWatermarkHeight));
 
                 for (int k = 0; k < textLines.length; ++k) {
                     contentStream.showText(textLines[k]);