x axis log scale.

[dygraphs.git] / dygraph-interaction-model.js

diff --git a/dygraph-interaction-model.js b/dygraph-interaction-model.js
index 9afc3c1..56491e1 100644 (file)
--- a/dygraph-interaction-model.js
+++ b/dygraph-interaction-model.js
@@ -38,8 +38,14 @@ Dygraph.Interaction.startPan = function(event, g, context) {
   var i, axis;
   context.isPanning = true;
   var xRange = g.xAxisRange();
-  context.dateRange = xRange[1] - xRange[0];
-  context.initialLeftmostDate = xRange[0];
+
+  if (g.getOptionForAxis("logscale", 'x')) {
+    context.initialLeftmostDate = Dygraph.log10(xRange[0]);
+    context.dateRange = Dygraph.log10(xRange[1]) - Dygraph.log10(xRange[0]);
+  } else {
+    context.initialLeftmostDate = xRange[0];    
+    context.dateRange = xRange[1] - xRange[0];
+  }
   context.xUnitsPerPixel = context.dateRange / (g.plotter_.area.w - 1);
 
   if (g.attr_("panEdgeFraction")) {
@@ -63,8 +69,8 @@ Dygraph.Interaction.startPan = function(event, g, context) {
       var boundedTopY = g.toDomYCoord(yExtremes[0], i) + maxYPixelsToDraw;
       var boundedBottomY = g.toDomYCoord(yExtremes[1], i) - maxYPixelsToDraw;
 
-      var boundedTopValue = g.toDataYCoord(boundedTopY);
-      var boundedBottomValue = g.toDataYCoord(boundedBottomY);
+      var boundedTopValue = g.toDataYCoord(boundedTopY, i);
+      var boundedBottomValue = g.toDataYCoord(boundedBottomY, i);
 
       boundedValues[i] = [boundedTopValue, boundedBottomValue];
     }
@@ -132,16 +138,22 @@ Dygraph.Interaction.movePan = function(event, g, context) {
     }
   }
 
-  g.dateWindow_ = [minDate, maxDate];
+  if (g.getOptionForAxis("logscale", 'x')) {
+    g.dateWindow_ = [ Math.pow(Dygraph.LOG_SCALE, minDate),
+                      Math.pow(Dygraph.LOG_SCALE, maxDate) ];
+  } else {
+    g.dateWindow_ = [minDate, maxDate];    
+  }
 
   // y-axis scaling is automatic unless this is a full 2D pan.
   if (context.is2DPan) {
+
+    var pixelsDragged = context.dragEndY - context.dragStartY;
+
     // Adjust each axis appropriately.
     for (var i = 0; i < g.axes_.length; i++) {
       var axis = g.axes_[i];
       var axis_data = context.axes[i];
-
-      var pixelsDragged = context.dragEndY - context.dragStartY;
       var unitsDragged = pixelsDragged * axis_data.unitsPerPixel;
 
       var boundedValue = context.boundedValues ? context.boundedValues[i] : null;
@@ -159,8 +171,7 @@ Dygraph.Interaction.movePan = function(event, g, context) {
           minValue = maxValue - axis_data.dragValueRange;
         }
       }
-      var logscale = g.attributes_.getForAxis("logscale", i);
-      if (logscale) {
+      if (g.attributes_.getForAxis("logscale", i)) {
         axis.valueWindow = [ Math.pow(Dygraph.LOG_SCALE, minValue),
                              Math.pow(Dygraph.LOG_SCALE, maxValue) ];
       } else {
@@ -342,13 +353,27 @@ Dygraph.Interaction.endZoom = function(event, g, context) {
     Dygraph.Interaction.treatMouseOpAsClick(g, event, context);
   }
 
+  // The zoom rectangle is visibly clipped to the plot area, so its behavior
+  // should be as well.
+  // See http://code.google.com/p/dygraphs/issues/detail?id=280
+  var plotArea = g.getArea();
   if (regionWidth >= 10 && context.dragDirection == Dygraph.HORIZONTAL) {
-    g.doZoomX_(Math.min(context.dragStartX, context.dragEndX),
-               Math.max(context.dragStartX, context.dragEndX));
+    var left = Math.min(context.dragStartX, context.dragEndX),
+        right = Math.max(context.dragStartX, context.dragEndX);
+    left = Math.max(left, plotArea.x);
+    right = Math.min(right, plotArea.x + plotArea.w);
+    if (left < right) {
+      g.doZoomX_(left, right);
+    }
     context.cancelNextDblclick = true;
   } else if (regionHeight >= 10 && context.dragDirection == Dygraph.VERTICAL) {
-    g.doZoomY_(Math.min(context.dragStartY, context.dragEndY),
-               Math.max(context.dragStartY, context.dragEndY));
+    var top = Math.min(context.dragStartY, context.dragEndY),
+        bottom = Math.max(context.dragStartY, context.dragEndY);
+    top = Math.max(top, plotArea.y);
+    bottom = Math.min(bottom, plotArea.y + plotArea.h);
+    if (top < bottom) {
+      g.doZoomY_(top, bottom);
+    }
     context.cancelNextDblclick = true;
   } else {
     if (context.zoomMoved) g.clearZoomRect_();
@@ -596,6 +621,7 @@ Dygraph.Interaction.defaultModel = {
     if (context.isZooming) {
       context.dragEndX = null;
       context.dragEndY = null;
+      g.clearZoomRect_();
     }
   },