Do not perform redundant mathematical operations that can cause the precission loss. Introduce some new handy UV methods.

DEVSIX-1810

Author: ars18wrw

layout/src/main/java/com/itextpdf/layout/renderer/AbstractRenderer.java

@@ -1412,7 +1412,9 @@ protected Float retrieveUnitValue(float baseValue, int property, boolean pointOn
         }
         if (value != null) {
             if (value.getUnitType() == UnitValue.PERCENT) {
-                return baseValue * value.getValue() / 100;
+                // during mathematical operations the precision can be lost, so avoiding them if possible (100 / 100 == 1) is a good practice
+                // TODO Maybe decrease the result value by AbstractRenderer.EPS ?
+                return value.getValue() != 100 ? baseValue * value.getValue() / 100 : baseValue;
             } else {
                 assert value.getUnitType() == UnitValue.POINT;
                 return value.getValue();
@@ -2046,6 +2048,17 @@ protected boolean hasAbsoluteUnitValue(int property) {
         return value != null && value.isPointValue();
     }
 
+    /**
+     * Check if corresponding property has relative value.
+     *
+     * @param property {@link Property}
+     * @return false if property value either null, or point, otherwise true.
+     */
+    protected boolean hasRelativeUnitValue(int property) {
+        UnitValue value = this.<UnitValue>getProperty(property);
+        return value != null && value.isPercentValue();
+    }
+
     boolean isFirstOnRootArea(boolean checkRootAreaOnly) {
         boolean isFirstOnRootArea = true;
         IRenderer ancestor = this;