Merge pull request #16 from alfattack/page-break-inside

mstancombe · web-flow · commit 2da1da5c5019 · 2024-08-20T11:25:53.000+10:00
Page break inside improvement
diff --git a/Source/Demos/HtmlRenderer.Demo.Common/TestSamples/37. Breaking Pages 4 - Divs.htm b/Source/Demos/HtmlRenderer.Demo.Common/TestSamples/37. Breaking Pages 4 - Divs.htm
@@ -8,7 +8,7 @@
         This is on page 2
     </div>
 
-    <div style="height: 700px; background-color: red;">
+    <div style="height: 400px; background-color: red;">
         This is on page 3.
     </div>
 
@@ -18,8 +18,11 @@
         <div style="height: 500px; background-color: yellow;">
             This is also on page 4
         </div>
+        <div style="height: 100px; background-color: brown; page-break-inside: avoid;">
+            This is also on page 4.
+        </div>
 
-        <div style="height: 400px; background-color: aqua; page-break-inside: avoid;">
+        <div style="height: 700px; background-color: aqua; page-break-inside: avoid;">
             This is on page 5
         </div>
     </div>
@@ -29,8 +32,7 @@
             This is on page 6
         </div>
 
-        <div style="background-color:yellowgreen;width:90px;height: 1000px;">
-        </div>
+        <div style="background-color: yellowgreen; width: 90px; height: 1000px;"></div>
     </div>
 
 </body>
diff --git a/Source/Demos/HtmlRenderer.Demo.Common/TestSamples/38. Breaking Pages 5 - Divs.htm b/Source/Demos/HtmlRenderer.Demo.Common/TestSamples/38. Breaking Pages 5 - Divs.htm
@@ -0,0 +1,10 @@
+﻿<html>
+<body>
+    <div style="height: 700px; background-color: indianred;">
+        This is on page 1
+    </div>
+    <div style="background-color: orange; page-break-inside: avoid;">
+        <div style="background-color: yellowgreen; width: 90px; height: 1000px;"></div>
+    </div>
+</body>
+</html>
diff --git a/Source/Demos/HtmlRenderer.Demo.Common/TestSamples/39. Absolute position.htm b/Source/Demos/HtmlRenderer.Demo.Common/TestSamples/39. Absolute position.htm
diff --git a/Source/Demos/HtmlRenderer.Demo.Console/Program.cs b/Source/Demos/HtmlRenderer.Demo.Console/Program.cs
@@ -24,7 +24,7 @@
 foreach (var htmlSample in samples)
 {
     ////Just doing one test here.  Comment this for all of them.
-    if (!htmlSample.FullName.Contains("38")) continue;
+    if (!htmlSample.FullName.Contains("37")) continue;
 
     //await skia.GenerateSampleAsync(htmlSample);
     //await svgSkia.GenerateSampleAsync(htmlSample);
diff --git a/Source/HtmlRenderer/Core/Dom/CssBox.cs b/Source/HtmlRenderer/Core/Dom/CssBox.cs
@@ -624,6 +624,7 @@ public virtual void Dispose()
         /// <param name="g">Device context to use</param>
         protected virtual async Task PerformLayoutImpAsync(RGraphics g)
         {
+            var prevSibling = DomUtils.GetPreviousSibling(this);
             if (Display != CssConstants.None)
             {
                 RectanglesReset();
@@ -652,7 +653,6 @@ protected virtual async Task PerformLayoutImpAsync(RGraphics g)
 
                 if (Display != CssConstants.TableCell)
                 {
-                    var prevSibling = DomUtils.GetPreviousSibling(this);
                     double left;
                     double top;
 
@@ -695,17 +695,19 @@ protected virtual async Task PerformLayoutImpAsync(RGraphics g)
                                 : 0);
 
                         Location = new RPoint(left, top);
-                        
+
                         if (this.PageBreakBefore == CssConstants.Always || prevSibling?.PageBreakAfter == CssConstants.Always)
                         {
                             this.BreakPage(true);
                         }
-                        else if (this.PageBreakInside == CssConstants.Avoid
-                            && ActualHeight + Location.Y > HtmlContainer.PageSize.Height
-                            && prevSibling != null)
+                        else if (this.PageBreakInside == CssConstants.Avoid && prevSibling != null)
                         {
                             // handle page break avoiding.
-                            this.BreakPage(true);
+                            var pageLocationY = Location.Y % HtmlContainer.PageSize.Height;
+                            if (ActualHeight + pageLocationY > HtmlContainer.PageSize.Height)
+                            {
+                                this.BreakPage(true);
+                            }
                         }
 
                         //Start with the assumption this is zero height.
@@ -739,7 +741,6 @@ protected virtual async Task PerformLayoutImpAsync(RGraphics g)
             }
             else
             {
-                var prevSibling = DomUtils.GetPreviousSibling(this);
                 if (prevSibling != null)
                 {
                     if (Location == RPoint.Empty)

Original file line number	Diff line number	Diff line change
`@@ -24,7 +24,7 @@`
`24`	`24`	`foreach (var htmlSample in samples)`
`25`	`25`	`{`
`26`	`26`	`////Just doing one test here. Comment this for all of them.`
`27`		`- if (!htmlSample.FullName.Contains("38")) continue;`
	`27`	`+ if (!htmlSample.FullName.Contains("37")) continue;`
`28`	`28`
`29`	`29`	`//await skia.GenerateSampleAsync(htmlSample);`
`30`	`30`	`//await svgSkia.GenerateSampleAsync(htmlSample);`
Original file line number	Diff line number	Diff line change
`@@ -624,6 +624,7 @@ public virtual void Dispose()`
`624`	`624`	`/// <param name="g">Device context to use</param>`
`625`	`625`	`protected virtual async Task PerformLayoutImpAsync(RGraphics g)`
`626`	`626`	`{`
	`627`	`+ var prevSibling = DomUtils.GetPreviousSibling(this);`
`627`	`628`	`if (Display != CssConstants.None)`
`628`	`629`	`{`
`629`	`630`	`RectanglesReset();`
`@@ -652,7 +653,6 @@ protected virtual async Task PerformLayoutImpAsync(RGraphics g)`
`652`	`653`
`653`	`654`	`if (Display != CssConstants.TableCell)`
`654`	`655`	`{`
`655`		`- var prevSibling = DomUtils.GetPreviousSibling(this);`
`656`	`656`	`double left;`
`657`	`657`	`double top;`
`658`	`658`
`@@ -695,17 +695,19 @@ protected virtual async Task PerformLayoutImpAsync(RGraphics g)`
`695`	`695`	`: 0);`
`696`	`696`
`697`	`697`	`Location = new RPoint(left, top);`
`698`		`-`
	`698`	`+`
`699`	`699`	`if (this.PageBreakBefore == CssConstants.Always \|\| prevSibling?.PageBreakAfter == CssConstants.Always)`
`700`	`700`	`{`
`701`	`701`	`this.BreakPage(true);`
`702`	`702`	`}`
`703`		`- else if (this.PageBreakInside == CssConstants.Avoid`
`704`		`- && ActualHeight + Location.Y > HtmlContainer.PageSize.Height`
`705`		`- && prevSibling != null)`
	`703`	`+ else if (this.PageBreakInside == CssConstants.Avoid && prevSibling != null)`
`706`	`704`	`{`
`707`	`705`	`// handle page break avoiding.`
`708`		`- this.BreakPage(true);`
	`706`	`+ var pageLocationY = Location.Y % HtmlContainer.PageSize.Height;`
	`707`	`+ if (ActualHeight + pageLocationY > HtmlContainer.PageSize.Height)`
	`708`	`+ {`
	`709`	`+ this.BreakPage(true);`
	`710`	`+ }`
`709`	`711`	`}`
`710`	`712`
`711`	`713`	`//Start with the assumption this is zero height.`
`@@ -739,7 +741,6 @@ protected virtual async Task PerformLayoutImpAsync(RGraphics g)`
`739`	`741`	`}`
`740`	`742`	`else`
`741`	`743`	`{`
`742`		`- var prevSibling = DomUtils.GetPreviousSibling(this);`
`743`	`744`	`if (prevSibling != null)`
`744`	`745`	`{`
`745`	`746`	`if (Location == RPoint.Empty)`