Merge branch 'textBaseline'

lib/canvas.js

@@ -41,6 +41,12 @@ exports.cairoVersion = cairoVersion;
 
 var cache = {};
 
+/**
+ * Text baselines.
+ */
+
+var baselines = ['alphabetic', 'top', 'bottom', 'middle', 'ideographic', 'hanging'];
+
 /**
  * Font RegExp helpers.
  */
@@ -502,6 +508,30 @@ Context2d.prototype.__defineGetter__('font', function(){
   return this.lastFontString || '10px sans-serif';
 });
 
+/**
+ * Set text baseline.
+ *
+ * @api public
+ */
+
+Context2d.prototype.__defineSetter__('textBaseline', function(val){
+  var n = baselines.indexOf(val);
+  if (~n) {
+    this.lastBaseline = val;
+    this.setTextBaseline(n);
+  }
+});
+
+/**
+ * Get the current baseline setting.
+ *
+ * @api public
+ */
+
+Context2d.prototype.__defineGetter__('textAlign', function(){
+  return this.lastBaseline || 'alphabetic';
+});
+
 /**
  * Set text alignment.
  *

src/CanvasRenderingContext2d.cc

@@ -59,6 +59,19 @@ using namespace node;
   int width = args[2]->Int32Value(); \
   int height = args[3]->Int32Value();
 
+/*
+ * Text baselines.
+ */
+
+enum {
+    TEXT_BASELINE_ALPHABETIC
+  , TEXT_BASELINE_TOP
+  , TEXT_BASELINE_BOTTOM
+  , TEXT_BASELINE_MIDDLE
+  , TEXT_BASELINE_IDEOGRAPHIC
+  , TEXT_BASELINE_HANGING
+};
+
 /*
  * Initialize Context2d.
  */
@@ -88,6 +101,7 @@ Context2d::Initialize(Handle<Object> target) {
   NODE_SET_PROTOTYPE_METHOD(t, "strokeRect", StrokeRect);
   NODE_SET_PROTOTYPE_METHOD(t, "clearRect", ClearRect);
   NODE_SET_PROTOTYPE_METHOD(t, "rect", Rect);
+  NODE_SET_PROTOTYPE_METHOD(t, "setTextBaseline", SetTextBaseline);
   NODE_SET_PROTOTYPE_METHOD(t, "setTextAlignment", SetTextAlignment);
   NODE_SET_PROTOTYPE_METHOD(t, "setTextPath", SetTextPath);
   NODE_SET_PROTOTYPE_METHOD(t, "measureText", MeasureText);
@@ -868,6 +882,21 @@ Context2d::MeasureText(const Arguments &args) {
   return scope.Close(obj);
 }
 
+/*
+ * Set text baseline.
+ */
+
+Handle<Value>
+Context2d::SetTextBaseline(const Arguments &args) {
+  HandleScope scope;
+
+  if (!args[0]->IsInt32()) return Undefined();
+  Context2d *context = ObjectWrap::Unwrap<Context2d>(args.This());
+  context->state->textBaseline = args[0]->Int32Value();
+
+  return Undefined();
+}
+
 /*
  * Set text alignment. -1 0 1
  */
@@ -883,7 +912,6 @@ Context2d::SetTextAlignment(const Arguments &args) {
   return Undefined();
 }
 
-
 /*
  * Set text path at x, y.
  */
@@ -921,6 +949,21 @@ Context2d::SetTextPath(const Arguments &args) {
       break;
   }
 
+  // Baseline approx
+  // TODO:
+  switch (context->state->textBaseline) {
+    case TEXT_BASELINE_TOP:
+    case TEXT_BASELINE_HANGING:
+      y += te.height;
+      break;
+    case TEXT_BASELINE_MIDDLE:
+      y += te.height / 2;
+      break;
+    case TEXT_BASELINE_BOTTOM:
+      y -= te.height / 2;
+      break;
+  }
+
   cairo_move_to(ctx, x, y);
   cairo_text_path(ctx, *str);
 

src/CanvasRenderingContext2d.h

@@ -33,6 +33,7 @@ typedef struct {
   cairo_pattern_t *strokePattern;
   float globalAlpha;
   short textAlignment;
+  short textBaseline;
 } canvas_state_t;
 
 class Context2d: public node::ObjectWrap {
@@ -65,6 +66,7 @@ class Context2d: public node::ObjectWrap {
     static Handle<Value> SetShadowRGBA(const Arguments &args);
     static Handle<Value> SetFillPattern(const Arguments &args);
     static Handle<Value> SetStrokePattern(const Arguments &args);
+    static Handle<Value> SetTextBaseline(const Arguments &args);
     static Handle<Value> SetTextAlignment(const Arguments &args);
     static Handle<Value> SetTextPath(const Arguments &args);
     static Handle<Value> MeasureText(const Arguments &args);