From 7e3cd48b46813a121ae6454c955d1db7609627a9 Mon Sep 17 00:00:00 2001
From: wellenvogel <andreas@wellenvogel.de>
Date: Thu, 12 Sep 2024 20:01:03 +0200
Subject: [PATCH] #373: handle courses outside of 0...360 for text offsets, use
 the target rotation instead of always COG

---
 viewer/map/aislayer.js | 25 ++++++++++++++-----------
 1 file changed, 14 insertions(+), 11 deletions(-)

diff --git a/viewer/map/aislayer.js b/viewer/map/aislayer.js
index 0fe0ebf8..b769c8d0 100644
--- a/viewer/map/aislayer.js
+++ b/viewer/map/aislayer.js
@@ -437,8 +437,6 @@ AisLayer.prototype.drawTargetSymbol=function(drawing,xy,target,drawTargetFunctio
     let lostTime=globalStore.getData(keys.properties.aisLostTime,0);
     let minDRspeed=globalStore.getData(keys.properties.aisMinDisplaySpeed,0);
     // own ship
-    let lat=globalStore.getData(keys.nav.gps.lat,0);
-    let lon=globalStore.getData(keys.nav.gps.lon,0);
     let cog=globalStore.getData(keys.nav.gps.course,0);
     let sog=globalStore.getData(keys.nav.gps.speed,0);
     // ais target
@@ -542,10 +540,10 @@ AisLayer.prototype.drawTargetSymbol=function(drawing,xy,target,drawTargetFunctio
         }
     }
     let curpix=drawing.drawImageToContext(xy,symbol.image,style);
-    return {pix:curpix, scale:scale, style: style};
+    return {pix:curpix, scale:scale, style: style, rot: target_hdg};
 };
 
-AisLayer.prototype.computeTextOffsets=function(drawing, target,textIndex, opt_baseOffset,opt_iconScale){
+AisLayer.prototype.computeTextOffsets=function(drawing, targetRot,textIndex, opt_baseOffset,opt_iconScale){
     let scale=(opt_iconScale === undefined)?1:opt_iconScale;
     let rt=[opt_baseOffset?opt_baseOffset[0]:10,opt_baseOffset?opt_baseOffset[1]:0];
     amul(rt,scale);
@@ -554,17 +552,22 @@ AisLayer.prototype.computeTextOffsets=function(drawing, target,textIndex, opt_ba
     if (drawing.getUseHdpi()){
         hoffset*=drawing.getDevPixelRatio();
     }
-    if (! target.course || (0 <= target.course  &&  target.course < 90 )){
+    let course=targetRot;
+    if (course){
+        while (course > 360) course-=360;
+        while (course < 0) course+=360;
+    }
+    if (! course || (0 <= course  &&  course < 90 )){
         rt[1]+=(textIndex+0.5)*hoffset;
     }
     else{
-        if (target.course >= 90 && target.course < 180){
+        if (course >= 90 && course < 180){
             rt[1]+=-(textIndex+0.5)*hoffset;
         }
-        if (target.course >= 180 && target.course < 270){
+        if (course >= 180 && course < 270){
             rt[1]+=(textIndex+0.5)*hoffset;
         }
-        if (target.course >= 270 && target.course < 360){
+        if (course >= 270 && course < 360){
             rt[1]+=-(textIndex+0.5)*hoffset;
         }
     }
@@ -603,18 +606,18 @@ AisLayer.prototype.onPostCompose=function(center,drawing){
         let textOffsetScale=drawn.scale;
         let text=AisFormatter.format(firstLabel,current,true);
         if (text) {
-            drawing.drawTextToContext(pos, text, assign({}, this.textStyle, this.computeTextOffsets(drawing,current, 0,drawn.style.textOffset,textOffsetScale),alpha));
+            drawing.drawTextToContext(pos, text, assign({}, this.textStyle, this.computeTextOffsets(drawing,drawn.rot, 0,drawn.style.textOffset,textOffsetScale),alpha));
         }
         if (secondLabel !== firstLabel) {
             text=AisFormatter.format(secondLabel,current,true);
             if (text) {
-                drawing.drawTextToContext(pos, text, assign({}, this.textStyle, this.computeTextOffsets(drawing,current, 1,drawn.style.textOffset,textOffsetScale),alpha));
+                drawing.drawTextToContext(pos, text, assign({}, this.textStyle, this.computeTextOffsets(drawing,drawn.rot, 1,drawn.style.textOffset,textOffsetScale),alpha));
             }
         }
         if (thirdLabel !== firstLabel && thirdLabel !== secondLabel){
             text=AisFormatter.format(thirdLabel,current,true);
             if (text) {
-                drawing.drawTextToContext(pos, text, assign({}, this.textStyle, this.computeTextOffsets(drawing,current, 2,drawn.style.textOffset,textOffsetScale),alpha));
+                drawing.drawTextToContext(pos, text, assign({}, this.textStyle, this.computeTextOffsets(drawing,drawn.rot, 2,drawn.style.textOffset,textOffsetScale),alpha));
             }
         }
     }