[SVGDom] Add support for assorted absolute units

R=robertphillips@google.com,stephana@google.com
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2259473002

Review-Url: https://codereview.chromium.org/2259473002

diff --git a/experimental/svg/model/SkSVGRenderContext.cpp b/experimental/svg/model/SkSVGRenderContext.cpp
index 8ad8814..4a1d77d 100644 (file)
--- a/experimental/svg/model/SkSVGRenderContext.cpp
+++ b/experimental/svg/model/SkSVGRenderContext.cpp
@@ -26,6 +26,13 @@ SkScalar length_size_for_type(const SkSize& viewport, SkSVGLengthContext::Length
     return 0;
 }
 
+// Multipliers for DPI-relative units.
+constexpr SkScalar kINMultiplier = 1.00f;
+constexpr SkScalar kPTMultiplier = kINMultiplier / 72.272f;
+constexpr SkScalar kPCMultiplier = kPTMultiplier * 12;
+constexpr SkScalar kMMMultiplier = kINMultiplier / 25.4f;
+constexpr SkScalar kCMMultiplier = kMMMultiplier * 10;
+
 } // anonymous ns
 
 SkScalar SkSVGLengthContext::resolve(const SkSVGLength& l, LengthType t) const {
@@ -36,6 +43,16 @@ SkScalar SkSVGLengthContext::resolve(const SkSVGLength& l, LengthType t) const {
         return l.value();
     case SkSVGLength::Unit::kPercentage:
         return l.value() * length_size_for_type(fViewport, t) / 100;
+    case SkSVGLength::Unit::kCM:
+        return l.value() * fDPI * kCMMultiplier;
+    case SkSVGLength::Unit::kMM:
+        return l.value() * fDPI * kMMMultiplier;
+    case SkSVGLength::Unit::kIN:
+        return l.value() * fDPI * kINMultiplier;
+    case SkSVGLength::Unit::kPT:
+        return l.value() * fDPI * kPTMultiplier;
+    case SkSVGLength::Unit::kPC:
+        return l.value() * fDPI * kPCMultiplier;
     default:
         SkDebugf("unsupported unit type: <%d>\n", l.unit());
         return 0;

diff --git a/experimental/svg/model/SkSVGRenderContext.h b/experimental/svg/model/SkSVGRenderContext.h
index e6df725..61f8746 100644 (file)
--- a/experimental/svg/model/SkSVGRenderContext.h
+++ b/experimental/svg/model/SkSVGRenderContext.h
@@ -20,7 +20,8 @@ class SkSVGLength;
 
 class SkSVGLengthContext {
 public:
-    SkSVGLengthContext(const SkSize& viewport) : fViewport(viewport) {}
+    SkSVGLengthContext(const SkSize& viewport, SkScalar dpi = 90)
+        : fViewport(viewport), fDPI(dpi) {}
 
     enum class LengthType {
         kHorizontal,
@@ -36,7 +37,8 @@ public:
                          const SkSVGLength& w, const SkSVGLength& h) const;
 
 private:
-    SkSize fViewport;
+    SkSize   fViewport;
+    SkScalar fDPI;
 };
 
 struct SkSVGPresentationContext {