I can set up 3D lines in a COLLADA .dae file and view them in Google Earth, but they are really thin and very hard to see over Colorado. How can I set the line width to something other than the default of 1 (meter?)? I have located the line_width tag in the COLLADA documentation, but it does not seem to do anything no matter where I put it.
Here is my .dae file Lines-blue.dae.
<?xml version="1.0"?>
<COLLADA xmlns="http://www.collada.org/2005/11/COLLADASchema" version="1.4.1">
<asset>
<contributor>
<author>Carl Drews</author>
<authoring_tool>Assimp Collada Exporter</authoring_tool>
</contributor>
<created>2000-01-01T23:59:59</created>
<modified>2000-01-01T23:59:59</modified>
<unit name="meter" meter="1" />
<up_axis>Z_UP</up_axis>
</asset>
<library_effects>
<effect id="m0DefaultMaterial-fx" name="m0DefaultMaterial">
<profile_COMMON>
<technique sid="standard">
<phong>
<emission>
<color sid="emission">0 0 0 1</color>
</emission>
<ambient>
<color sid="ambient">0.05 0.05 0.05 1</color>
</ambient>
<diffuse>
<color sid="diffuse">0 0 1 1</color>
</diffuse>
<specular>
<color sid="specular">0 0 0 1</color>
</specular>
<shininess>
<float sid="shininess">16</float>
</shininess>
<reflective>
<color sid="reflective">0 0 0 0</color>
</reflective>
<transparency>
<float sid="transparency">0.5</float>
</transparency>
</phong>
</technique>
<extra>
<technique profile="GOOGLEEARTH">
<double_sided>1</double_sided>
**<line_width>1200.0</line_width>**
</technique>
</extra>
</profile_COMMON>
</effect>
</library_effects>
<library_materials>
<material id="m0DefaultMaterial" name="m0DefaultMaterial">
<instance_effect url="#m0DefaultMaterial-fx"/>
</material>
</library_materials>
<library_geometries>
<geometry id="meshId0" name="meshId0_name" >
<mesh>
<source id="meshId0-positions" name="meshId0-positions">
<float_array id="meshId0-positions-array" count="36">
0 0 0
12000 0 0
6000 6000 6000
12000 0 0
12000 12000 0
6000 6000 6000
12000 12000 0
0 12000 0
6000 6000 6000
0 12000 0
0 0 0
6000 6000 6000
</float_array>
<technique_common>
<accessor count="12" offset="0" source="#meshId0-positions-array" stride="3">
<param name="X" type="float" />
<param name="Y" type="float" />
<param name="Z" type="float" />
</accessor>
</technique_common>
</source>
<source id="meshId0-normals" name="meshId0-normals">
<float_array id="meshId0-normals-array" count="36">
0 -0.5 0.5
0 -0.5 0.5
0 -0.5 0.5
-0.5 0 0.5
-0.5 0 0.5
-0.5 0 0.5
0 0.5 0.5
0 0.5 0.5
0 0.5 0.5
-0.5 0 0.5
-0.5 0 0.5
-0.5 0 0.5
</float_array>
<technique_common>
<accessor count="12" offset="0" source="#meshId0-normals-array" stride="3">
<param name="X" type="float" />
<param name="Y" type="float" />
<param name="Z" type="float" />
</accessor>
</technique_common>
</source>
<vertices id="meshId0-vertices">
<input semantic="POSITION" source="#meshId0-positions" />
<input semantic="NORMAL" source="#meshId0-normals" />
</vertices>
<lines count="4" material="theresonlyone">
<input offset="0" semantic="VERTEX" source="#meshId0-vertices" />
<vcount>3 3 3 3</vcount>
<p>0 1 2
3 4 5
6 7 8
9 10 11
</p>
</lines>
</mesh>
</geometry>
</library_geometries>
<library_visual_scenes>
<visual_scene id="myScene" name="myScene">
<node id="STL_BINARY" name="STL_BINARY">
<matrix>1 0 0 0
0 1 0 0
0 0 1 0
0 0 0 1</matrix>
<instance_geometry url="#meshId0">
<bind_material>
<technique_common>
<instance_material symbol="theresonlyone" target="#m0DefaultMaterial"/>
</technique_common>
</bind_material>
</instance_geometry>
</node>
</visual_scene>
</library_visual_scenes>
<scene>
<instance_visual_scene url="#myScene" />
</scene>
</COLLADA>
Here is the KML fragment that includes the COLLADA Model:
<Style id="WideLine">
<LineStyle>
<width>100</width>
</LineStyle>
</Style>
<Placemark>
<name>Experimental white lines floating over Boulder.</name>
<description>Model created by Carl Drews - November 18, 2022.</description>
<Camera>
<longitude>-105.1000</longitude>
<latitude> 40.0650</latitude>
<altitude>2000</altitude>
<tilt>90.00</tilt>
<heading>-90.00</heading>
</Camera>
<Style id="default">
<styleUrl>#WideLine</styleUrl>
</Style>
<Model id="model_7">
<altitudeMode>relativeToGround</altitudeMode>
<Location>
<longitude>-104.9000</longitude>
<latitude> 39.7000</latitude>
<altitude>1000</altitude>
</Location>
<Orientation>
<heading>0</heading>
<tilt>0</tilt>
<roll>0</roll>
</Orientation>
<Scale>
<x>1</x>
<y>1</y>
<z>1</z>
</Scale>
<Link>
<href>Lines-blue.dae</href>
</Link>
</Model>
<TimeSpan>
<begin>2021-04-09T00:00:00Z</begin>
<end>2021-04-11T00:00:00Z</end>
</TimeSpan>
</Placemark>
These lines in 3D space are supposed to trace the contours of 3D isosurfaces that I have already created with COLLADA and displayed with Google Earth. But the lines won’t show up unless they are thicker or wider. I could create lines in pure KML (no .dae) but I don’t think they will lay down on my isosurfaces accurately enough.
Thank you for any assistance you can provide.