Fix bs marks

android/src/main/java/com/github/fujianlian/klinechart/BaseKLineChartView.java

@@ -1100,8 +1100,14 @@ private void drawBuySellMark(java.util.Map<String, Object> markData, KLineEntity
         float candleHigh = candlestick.getHighPrice();
         float highY = yFromValue(candleHigh); // Same method used by MainDraw.drawCandle
 
-        // Circle properties - diameter should match candlestick width
-        float circleRadius = mPointWidth * 0.4f; // Use 80% of candlestick width for diameter
+        // Circle properties - diameter should match candlestick width, but never smaller
+        // than a dynamic floor of buySellMarkMinWidthMultiplier * the candle width when fully
+        // zoomed out. The on-screen candle width is mPointWidth * mScaleX, so at the most
+        // zoomed-out scale (mScaleXMin) it is mPointWidth * mScaleXMin; the floor stays
+        // constant regardless of zoom.
+        float candleWidthAtMaxZoomOut = mPointWidth * mScaleXMin;
+        float minCircleRadius = candleWidthAtMaxZoomOut * configManager.buySellMarkMinWidthMultiplier / 2f;
+        float circleRadius = Math.max(mPointWidth * 0.5f, minCircleRadius);
 
         // Position both marks above the candlestick, with collision avoidance
         float markCenterY;
@@ -1128,20 +1134,27 @@ private void drawBuySellMark(java.util.Map<String, Object> markData, KLineEntity
             circleColor = configManager.decreaseColor; // Use same color as decreasing candlesticks
         }
 
+        // The canvas is horizontally scaled by mScaleX (see drawK). Counter that scale
+        // around the mark's center so it stays a perfect circle at any zoom level
+        // instead of stretching into an ellipse.
+        canvas.save();
+        canvas.translate(candleX, markCenterY);
+        canvas.scale(1f / mScaleX, 1f);
+
         // Create paint for circle
         Paint circlePaint = new Paint(Paint.ANTI_ALIAS_FLAG);
         circlePaint.setColor(circleColor);
         circlePaint.setStyle(Paint.Style.FILL);
 
         // Draw circle
-        canvas.drawCircle(candleX, markCenterY, circleRadius, circlePaint);
+        canvas.drawCircle(0, 0, circleRadius, circlePaint);
 
         // Draw border
         Paint borderPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
         borderPaint.setColor(circleColor);
         borderPaint.setStyle(Paint.Style.STROKE);
         borderPaint.setStrokeWidth(2.0f);
-        canvas.drawCircle(candleX, markCenterY, circleRadius, borderPaint);
+        canvas.drawCircle(0, 0, circleRadius, borderPaint);
 
         // Draw text inside circle
         String markText = "buy".equals(type) ? "B" : "S";
@@ -1153,9 +1166,11 @@ private void drawBuySellMark(java.util.Map<String, Object> markData, KLineEntity
 
         // Calculate text position (center of circle)
         Paint.FontMetrics fontMetrics = textPaint.getFontMetrics();
-        float textY = markCenterY - (fontMetrics.ascent + fontMetrics.descent) / 2;
+        float textY = -(fontMetrics.ascent + fontMetrics.descent) / 2;
 
-        canvas.drawText(markText, candleX, textY, textPaint);
+        canvas.drawText(markText, 0, textY, textPaint);
+
+        canvas.restore();
     }
 
     public int dp2px(float dp) {

android/src/main/java/com/github/fujianlian/klinechart/HTKLineConfigManager.java

@@ -105,6 +105,10 @@ public class HTKLineConfigManager {
 
     public float minVisibleCandles = 5;
 
+    // Minimum buy/sell mark diameter expressed as a multiple of the candle width when
+    // fully zoomed out. The mark never shrinks below this floor regardless of zoom.
+    public float buySellMarkMinWidthMultiplier = 3;
+
     public int minuteVolumeCandleColor = Color.RED;
 
     public float minuteVolumeCandleWidth = 1.5f;
@@ -462,6 +466,11 @@ public void reloadOptionList(Map optionList) {
             this.minVisibleCandles = minVisibleCandlesValue.floatValue();
         }
 
+        Number buySellMarkMinWidthMultiplierValue = (Number)configList.get("buySellMarkMinWidthMultiplier");
+        if (buySellMarkMinWidthMultiplierValue != null) {
+            this.buySellMarkMinWidthMultiplier = buySellMarkMinWidthMultiplierValue.floatValue();
+        }
+
         this.fontFamily = (configList.get("fontFamily")).toString();
         this.textColor = ((Number) configList.get("textColor")).intValue();
         this.headerTextFontSize = ((Number)configList.get("headerTextFontSize")).floatValue();

android/src/main/java/com/github/fujianlian/klinechart/ScrollAndScaleView.java

@@ -34,7 +34,7 @@ public abstract class ScrollAndScaleView extends RelativeLayout implements
 
     protected float mScaleX = 1;
 
-    protected float mScaleXMax = 2f;
+    protected float mScaleXMax = 2.5f;
 
     protected float mScaleXMin = 0.5f;
 

example/utils/businessLogic.js

@@ -357,6 +357,8 @@ export const packOptionList = (modelArray, appState, shouldScrollToEnd = true, u
 		candleWidth: 6 * pixelRatio,
 		candleCornerRadius: candleCornerRadius * pixelRatio,
 		minVisibleCandles: minVisibleCandles || 5,
+		buySellMarkMinWidthMultiplier: 3, // Min mark diameter = N * candle width when fully zoomed out
+
 		minuteVolumeCandleColor: processColor(showVolumeChart ? COLOR(0.0941176, 0.509804, 0.831373, 0.501961) : 'transparent'),
 		minuteVolumeCandleWidth: showVolumeChart ? 2 * pixelRatio : 0,
 		macdCandleWidth: 1 * pixelRatio,

ios/Classes/HTKLineConfigManager.swift

@@ -136,6 +136,10 @@ class HTKLineConfigManager: NSObject {
 
     var minVisibleCandles: CGFloat = 5
 
+    // Minimum buy/sell mark diameter expressed as a multiple of the candle width when
+    // fully zoomed out. The mark never shrinks below this floor regardless of zoom.
+    var buySellMarkMinWidthMultiplier: CGFloat = 3
+
     var minuteVolumeCandleWidth: CGFloat = 0
 
     var _minuteVolumeCandleWidth: CGFloat = 0
@@ -451,6 +455,7 @@ class HTKLineConfigManager: NSObject {
         _macdCandleWidth = configList["macdCandleWidth"] as? CGFloat ?? 0
         candleCornerRadius = configList["candleCornerRadius"] as? CGFloat ?? 0
         minVisibleCandles = configList["minVisibleCandles"] as? CGFloat ?? 5
+        buySellMarkMinWidthMultiplier = configList["buySellMarkMinWidthMultiplier"] as? CGFloat ?? 3
         reloadScrollViewScale(1)
         paddingTop = configList["paddingTop"] as? CGFloat ?? 0
         paddingRight = configList["paddingRight"] as? CGFloat ?? 0

ios/Classes/HTKLineView.swift

@@ -976,8 +976,15 @@ class HTKLineView: UIScrollView {
         let normalizedPrice = (markPrice - mainMinMaxRange.lowerBound) / priceRange
         let markY = mainBaseY + mainHeight - CGFloat(normalizedPrice) * mainHeight
 
-        // Make circle radius match candlestick width (same as Android logic)
-        let circleRadius: CGFloat = configManager.itemWidth * 0.4 // 80% of candlestick width for diameter
+        // Make circle radius match candlestick width (same as Android logic), but never
+        // smaller than a dynamic floor of buySellMarkMinWidthMultiplier * the candle width
+        // when fully zoomed out. `_itemWidth` is the unscaled candle width and `minScale`
+        // (0.3, see pinchSelector) is the most zoomed-out scale, so the floor stays constant
+        // regardless of zoom.
+        let minScale: CGFloat = 0.3
+        let candleWidthAtMaxZoomOut = configManager._itemWidth * minScale
+        let minCircleRadius = candleWidthAtMaxZoomOut * configManager.buySellMarkMinWidthMultiplier / 2
+        let circleRadius: CGFloat = max(configManager.itemWidth * 0.4, minCircleRadius)
 
         // Position both marks above the candlestick, with collision avoidance
         let markCenterY: CGFloat