Adding support of viewport units to SVG

third_party/WebKit/Source/core/svg/SVGLengthContext.cpp

Index: third_party/WebKit/Source/core/svg/SVGLengthContext.cpp
diff --git a/third_party/WebKit/Source/core/svg/SVGLengthContext.cpp b/third_party/WebKit/Source/core/svg/SVGLengthContext.cpp
index f553158421f727b1c1c0d0772fdae44da33a1052..22b768839f3dbc38612b45138d2df0a4bdb956c8 100644
--- a/third_party/WebKit/Source/core/svg/SVGLengthContext.cpp
+++ b/third_party/WebKit/Source/core/svg/SVGLengthContext.cpp
@@ -26,6 +26,7 @@
 #include "core/css/CSSHelper.h"
 #include "core/css/CSSPrimitiveValue.h"
 #include "core/dom/NodeComputedStyle.h"
+#include "core/frame/FrameView.h"
 #include "core/layout/LayoutObject.h"
 #include "core/style/ComputedStyle.h"
 #include "core/svg/SVGSVGElement.h"
@@ -101,6 +102,26 @@ static float convertValueFromEMSToUserUnits(const ComputedStyle* style, float va
     return value * style->specifiedFontSize();
 }
 
+static float viewportWidthPercent(const FloatSize& viewportSize)

[rwlbuis, 2015/12/22 16:41:49]

These 4 helper functions should be inline and should move to just above where
they are used.

[Shanmuga Pandi, 2015/12/23 09:00:59]

Done.

+{
+    return viewportSize.width() / 100;
+}
+
+static float viewportHeightPercent(const FloatSize& viewportSize)
+{
+    return viewportSize.height() / 100;
+}

[rwlbuis, 2015/12/22 16:41:49]

You can probably unify above two by passing a dimension, instead or
width/height. For instance something like a float widthOrHeight param.

[Shanmuga Pandi, 2015/12/23 09:00:59]

Done.

+
+static float viewportMinPercent(const FloatSize& viewportSize)
+{
+    return std::min(viewportSize.width(), viewportSize.height()) / 100;
+}
+
+static float viewportMaxPercent(const FloatSize& viewportSize)
+{
+    return std::max(viewportSize.width(), viewportSize.height()) / 100;
+}
+
 SVGLengthContext::SVGLengthContext(const SVGElement* context)
     : m_context(context)
 {
@@ -226,6 +247,12 @@ float SVGLengthContext::convertValueToUserUnits(float value, SVGLengthMode mode,
     case CSSPrimitiveValue::UnitType::Chs:
         userUnits = convertValueFromCHSToUserUnits(value);
         break;
+    case CSSPrimitiveValue::UnitType::ViewportWidth:
+    case CSSPrimitiveValue::UnitType::ViewportHeight:
+    case CSSPrimitiveValue::UnitType::ViewportMin:
+    case CSSPrimitiveValue::UnitType::ViewportMax:
+        userUnits = convertValueFromViewportUnitsToUserUnits(fromUnit, value);
+        break;
     default:
         ASSERT_NOT_REACHED();
         break;
@@ -273,6 +300,11 @@ float SVGLengthContext::convertValueFromUserUnits(float value, SVGLengthMode mod
         return value / cssPixelsPerPoint;
     case CSSPrimitiveValue::UnitType::Picas:
         return value / cssPixelsPerPica;
+    case CSSPrimitiveValue::UnitType::ViewportWidth:
+    case CSSPrimitiveValue::UnitType::ViewportHeight:
+    case CSSPrimitiveValue::UnitType::ViewportMin:
+    case CSSPrimitiveValue::UnitType::ViewportMax:
+        return convertValueFromUserUnitsToViewportUnits(toUnit, value);
     default:
         break;
     }
@@ -329,6 +361,70 @@ float SVGLengthContext::convertValueFromEXSToUserUnits(float value) const
     return value * ceilf(style->fontMetrics().xHeight() / style->effectiveZoom());
 }
 
+float SVGLengthContext::convertValueFromUserUnitsToViewportUnits(CSSPrimitiveValue::UnitType toUnit, float value) const

[rwlbuis, 2015/12/22 16:41:49]

Do we need to take zoom into account in these 2 methods?

[Shanmuga Pandi, 2015/12/23 09:00:59]

Acknowledged.

+{
+    if (!m_context)
+        return 0;
+
+    const Document& document = m_context->document();
+    FrameView* view = document.view();
+    if (!view)
+        return 0;
+
+    FloatSize viewportSize(view->width(), view->height());
+
+    switch (toUnit) {
+    case CSSPrimitiveValue::UnitType::ViewportWidth:
+        return value / viewportWidthPercent(viewportSize);
+
+    case CSSPrimitiveValue::UnitType::ViewportHeight:
+        return value / viewportHeightPercent(viewportSize);
+
+    case CSSPrimitiveValue::UnitType::ViewportMin:
+        return value / viewportMinPercent(viewportSize);
+
+    case CSSPrimitiveValue::UnitType::ViewportMax:
+        return value / viewportMaxPercent(viewportSize);
+    default:
+        break;
+    }
+
+    ASSERT_NOT_REACHED();
+    return 0;
+}
+
+float SVGLengthContext::convertValueFromViewportUnitsToUserUnits(CSSPrimitiveValue::UnitType fromUnit, float value) const
+{
+    if (!m_context)
+        return 0;
+
+    const Document& document = m_context->document();
+    FrameView* view = document.view();
+    if (!view)
+        return 0;
+
+    FloatSize viewportSize(view->width(), view->height());
+
+    switch (fromUnit) {
+    case CSSPrimitiveValue::UnitType::ViewportWidth:
+        return value * viewportWidthPercent(viewportSize);
+
+    case CSSPrimitiveValue::UnitType::ViewportHeight:
+        return value * viewportHeightPercent(viewportSize);
+
+    case CSSPrimitiveValue::UnitType::ViewportMin:
+        return value * viewportMinPercent(viewportSize);
+
+    case CSSPrimitiveValue::UnitType::ViewportMax:
+        return value * viewportMaxPercent(viewportSize);
+    default:
+        break;
+    }
+
+    ASSERT_NOT_REACHED();
+    return 0;
+}
+
 bool SVGLengthContext::determineViewport(FloatSize& viewportSize) const
 {
     if (!m_context)