Clip borders correctly to avoid zero-width lines. Fix cmps. Minor refactoring

DEVSIX-1311

Autoported commit.
Original commit hash: [a0c7e7f]

Author: ars18wrw

itext.tests/itext.layout.tests/resources/itext/layout/BlockTest/cmp_borderRadiusTest01.pdf

@@ -536,40 +536,46 @@ protected internal virtual bool ClipBorderArea(DrawContext drawContext, Rectangl
                 float right = outerBorderBox.GetRight();
                 float bottom = outerBorderBox.GetBottom();
                 float left = outerBorderBox.GetLeft();
+                float verticalRadius = Math.Min(outerBorderBox.GetHeight() / 2, radius);
+                float horizontalRadius = Math.Min(outerBorderBox.GetWidth() / 2, radius);
                 // radius border bbox
-                float x1 = right - radius;
-                float y1 = top - radius;
-                float x2 = right - radius;
-                float y2 = bottom + radius;
-                float x3 = left + radius;
-                float y3 = bottom + radius;
-                float x4 = left + radius;
-                float y4 = top - radius;
+                float x1 = right - horizontalRadius;
+                float y1 = top - verticalRadius;
+                float x2 = right - horizontalRadius;
+                float y2 = bottom + verticalRadius;
+                float x3 = left + horizontalRadius;
+                float y3 = bottom + verticalRadius;
+                float x4 = left + horizontalRadius;
+                float y4 = top - verticalRadius;
                 PdfCanvas canvas = drawContext.GetCanvas();
                 canvas.SaveState();
-                canvas.MoveTo(left, top).LineTo(x1, top).CurveTo(x1 + radius * curv, top, right, y1 + radius * curv, right
-                    , y1).LineTo(right, bottom).LineTo(left, bottom).LineTo(left, top);
+                // right top corner
+                canvas.MoveTo(left, top).LineTo(x1, top).CurveTo(x1 + horizontalRadius * curv, top, right, y1 + verticalRadius
+                     * curv, right, y1).LineTo(right, bottom).LineTo(left, bottom).LineTo(left, top);
                 canvas.Clip().NewPath();
-                canvas.MoveTo(right, top).LineTo(right, y2).CurveTo(right, y2 - radius * curv, x2 + radius * curv, bottom, 
-                    x2, bottom).LineTo(left, bottom).LineTo(left, top).LineTo(right, top);
+                // right bottom corner
+                canvas.MoveTo(right, top).LineTo(right, y2).CurveTo(right, y2 - verticalRadius * curv, x2 + horizontalRadius
+                     * curv, bottom, x2, bottom).LineTo(left, bottom).LineTo(left, top).LineTo(right, top);
                 canvas.Clip().NewPath();
-                canvas.MoveTo(right, bottom).LineTo(x3, bottom).CurveTo(x3 - radius * curv, bottom, left, y3 - radius * curv
-                    , left, y3).LineTo(left, top).LineTo(right, top).LineTo(right, bottom);
+                // left bottom corner
+                canvas.MoveTo(right, bottom).LineTo(x3, bottom).CurveTo(x3 - horizontalRadius * curv, bottom, left, y3 - verticalRadius
+                     * curv, left, y3).LineTo(left, top).LineTo(right, top).LineTo(right, bottom);
                 canvas.Clip().NewPath();
-                canvas.MoveTo(left, bottom).LineTo(left, y4).CurveTo(left, y4 + radius * curv, x4 - radius * curv, top, x4
-                    , top).LineTo(right, top).LineTo(right, bottom).LineTo(left, bottom);
+                // left top corner
+                canvas.MoveTo(left, bottom).LineTo(left, y4).CurveTo(left, y4 + verticalRadius * curv, x4 - horizontalRadius
+                     * curv, top, x4, top).LineTo(right, top).LineTo(right, bottom).LineTo(left, bottom);
                 canvas.Clip().NewPath();
                 Border[] borders = GetBorders();
-                float radiusTop = radius;
-                float radiusRight = radius;
-                float radiusBottom = radius;
-                float radiusLeft = radius;
-                float deltaTop = 0;
-                float deltaRight = 0;
-                float deltaBottom = 0;
-                float deltaLeft = 0;
+                float radiusTop = verticalRadius;
+                float radiusRight = horizontalRadius;
+                float radiusBottom = verticalRadius;
+                float radiusLeft = horizontalRadius;
+                float topBorderWidth = 0;
+                float rightBorderWidth = 0;
+                float bottomBorderWidth = 0;
+                float leftBorderWidth = 0;
                 if (borders[0] != null) {
-                    deltaTop = borders[0].GetWidth();
+                    topBorderWidth = borders[0].GetWidth();
                     top = top - borders[0].GetWidth();
                     if (y1 > top) {
                         y1 = top;
@@ -578,7 +584,7 @@ protected internal virtual bool ClipBorderArea(DrawContext drawContext, Rectangl
                     radiusTop = Math.Max(0, radiusTop - borders[0].GetWidth());
                 }
                 if (borders[1] != null) {
-                    deltaRight = borders[1].GetWidth();
+                    rightBorderWidth = borders[1].GetWidth();
                     right = right - borders[1].GetWidth();
                     if (x1 > right) {
                         x1 = right;
@@ -587,7 +593,7 @@ protected internal virtual bool ClipBorderArea(DrawContext drawContext, Rectangl
                     radiusRight = Math.Max(0, radiusRight - borders[1].GetWidth());
                 }
                 if (borders[2] != null) {
-                    deltaBottom = borders[2].GetWidth();
+                    bottomBorderWidth = borders[2].GetWidth();
                     bottom = bottom + borders[2].GetWidth();
                     if (x3 < left) {
                         x3 = left;
@@ -596,33 +602,33 @@ protected internal virtual bool ClipBorderArea(DrawContext drawContext, Rectangl
                     radiusBottom = Math.Max(0, radiusBottom - borders[2].GetWidth());
                 }
                 if (borders[3] != null) {
-                    deltaLeft = borders[3].GetWidth();
+                    leftBorderWidth = borders[3].GetWidth();
                     left = left + borders[3].GetWidth();
                     radiusLeft = Math.Max(0, radiusLeft - borders[3].GetWidth());
                 }
                 canvas.MoveTo(x1, top).CurveTo(x1 + Math.Min(radiusTop, radiusRight) * curv, top, right, y1 + Math.Min(radiusTop
-                    , radiusRight) * curv, right, y1).LineTo(x4, y1).LineTo(x4, top).LineTo(x1, top).LineTo(x1, top + deltaTop
-                    ).LineTo(left - deltaLeft, top + deltaTop).LineTo(left - deltaLeft, bottom - deltaBottom).LineTo(right
-                     + deltaRight, bottom - deltaBottom).LineTo(right + deltaRight, top + deltaTop).LineTo(x1, top + deltaTop
-                    );
+                    , radiusRight) * curv, right, y1).LineTo(right, y2).LineTo(x3, y2).LineTo(x3, top).LineTo(x1, top).LineTo
+                    (x1, top + topBorderWidth).LineTo(left - leftBorderWidth, top + topBorderWidth).LineTo(left - leftBorderWidth
+                    , bottom - bottomBorderWidth).LineTo(right + rightBorderWidth, bottom - bottomBorderWidth).LineTo(right
+                     + rightBorderWidth, top + topBorderWidth).LineTo(x1, top + topBorderWidth);
                 canvas.Clip().NewPath();
                 canvas.MoveTo(right, y2).CurveTo(right, y2 - Math.Min(radiusRight, radiusBottom) * curv, x2 + Math.Min(radiusRight
-                    , radiusBottom) * curv, bottom, x2, bottom).LineTo(x2, y1).LineTo(right, y1).LineTo(right, y2).LineTo(
-                    right + deltaRight, y2).LineTo(right + deltaRight, top + deltaTop).LineTo(left - deltaLeft, top + deltaTop
-                    ).LineTo(left - deltaLeft, bottom - deltaBottom).LineTo(right + deltaRight, bottom - deltaBottom).LineTo
-                    (right + deltaRight, y2);
+                    , radiusBottom) * curv, bottom, x2, bottom).LineTo(x3, bottom).LineTo(x3, y4).LineTo(right, y4).LineTo
+                    (right, y2).LineTo(right + rightBorderWidth, y2).LineTo(right + rightBorderWidth, top + topBorderWidth
+                    ).LineTo(left - leftBorderWidth, top + topBorderWidth).LineTo(left - leftBorderWidth, bottom - bottomBorderWidth
+                    ).LineTo(right + rightBorderWidth, bottom - bottomBorderWidth).LineTo(right + rightBorderWidth, y2);
                 canvas.Clip().NewPath();
                 canvas.MoveTo(x3, bottom).CurveTo(x3 - Math.Min(radiusBottom, radiusLeft) * curv, bottom, left, y3 - Math.
-                    Min(radiusBottom, radiusLeft) * curv, left, y3).LineTo(x2, y3).LineTo(x2, bottom).LineTo(x3, bottom).LineTo
-                    (x3, bottom - deltaBottom).LineTo(right + deltaRight, bottom - deltaBottom).LineTo(right + deltaRight, 
-                    top + deltaTop).LineTo(left - deltaLeft, top + deltaTop).LineTo(left - deltaLeft, bottom - deltaBottom
-                    ).LineTo(x3, bottom - deltaBottom);
+                    Min(radiusBottom, radiusLeft) * curv, left, y3).LineTo(left, y4).LineTo(x1, y4).LineTo(x1, bottom).LineTo
+                    (x3, bottom).LineTo(x3, bottom - bottomBorderWidth).LineTo(right + rightBorderWidth, bottom - bottomBorderWidth
+                    ).LineTo(right + rightBorderWidth, top + topBorderWidth).LineTo(left - leftBorderWidth, top + topBorderWidth
+                    ).LineTo(left - leftBorderWidth, bottom - bottomBorderWidth).LineTo(x3, bottom - bottomBorderWidth);
                 canvas.Clip().NewPath();
                 canvas.MoveTo(left, y4).CurveTo(left, y4 + Math.Min(radiusLeft, radiusTop) * curv, x4 - Math.Min(radiusLeft
-                    , radiusTop) * curv, top, x4, top).LineTo(x4, y3).LineTo(left, y3).LineTo(left, y4).LineTo(left - deltaLeft
-                    , y4).LineTo(left - deltaLeft, bottom - deltaBottom).LineTo(right + deltaRight, bottom - deltaBottom).
-                    LineTo(right + deltaRight, top + deltaTop).LineTo(left - deltaLeft, top + deltaTop).LineTo(left - deltaLeft
-                    , y4);
+                    , radiusTop) * curv, top, x4, top).LineTo(x1, top).LineTo(x1, y2).LineTo(left, y2).LineTo(left, y4).LineTo
+                    (left - leftBorderWidth, y4).LineTo(left - leftBorderWidth, bottom - bottomBorderWidth).LineTo(right +
+                     rightBorderWidth, bottom - bottomBorderWidth).LineTo(right + rightBorderWidth, top + topBorderWidth).
+                    LineTo(left - leftBorderWidth, top + topBorderWidth).LineTo(left - leftBorderWidth, y4);
                 canvas.Clip().NewPath();
             }
             return 0 != radius;

itext.tests/itext.layout.tests/resources/itext/layout/BlockTest/cmp_borderRadiusTest02.pdf

@@ -1 +1 @@
-9761a2eddde528939734a5c10db48712a65c4867
+a0c7e7fe25d17d5eaa6c1f31c3c8dd2eb656193b