IGraphicTracker.SetTransparency

Question

Hi all,

The docs for IGraphicTracker.SetTransparency include the line "This is used only in 2D mode and only if the graphic's symbol supports ISymbolEffects", which is all well and good except ISymbolEffects...doesn't seem to exist. ESRI's search engine turns up nothing, and Google only returns links to the API reference for .SetTransparency.

Using .SetTransparency in code doesn't seem to do anything. Does anyone know:
a) if this interface actually exists, or
b) it's possible to use transparency in the GraphicTracker, and if so....how?

cheers,
Paul

SteveShimazu · Answer

Hello,

Was there any resolution to this?  I am trying the same thing and I assume you would need to add the ISymbolEffects to the ISymbolPtr, but I do not see where ISymbolEffects exists.
     -Steve

PaulDowling1 · Answer

Hi Venkat,

Sorry - specifically I'm trying to do partial transparency for a polygon object. This works nicely when using a dynamic layer, via IDynamicSymbolProperties2.setColor(), but the GraphicTracker doesn't seem to have the equivalent....other than this ISymbolEffects thing that doesn't actually seem to exist.

Setting the .Transparency of the Color of a SimpleFillSymbol has no effect.

cheers,
Paul

Venkata_RaoTammineni · Answer

Hi all,

The docs for IGraphicTracker.SetTransparency include the line "This is used only in 2D mode and only if the graphic's symbol supports ISymbolEffects", which is all well and good except ISymbolEffects...doesn't seem to exist. ESRI's search engine turns up nothing, and Google only returns links to the API reference for .SetTransparency.

Using .SetTransparency in code doesn't seem to do anything. Does anyone know:
a) if this interface actually exists, or
b) it's possible to use transparency in the GraphicTracker, and if so....how?

cheers,
Paul

You might need to play with symbol...if you want to get transparency ..

public IGraphicTracker m_graphicTracker = null;
private void CreateGTSymbols()
        {
            if (m_graphicTracker == null)
                return;
            //1st point symbol
            IColor color = new RgbColorClass() { Red = 0, Green = 0, Blue = 255 };
            stdole.IFontDisp symbolFont = new stdole.StdFontClass() as stdole.IFontDisp;
            symbolFont.Name = "ESRI Default Marker";
            ICharacterMarkerSymbol characterMarkerSymbol = new CharacterMarkerSymbolClass();
            characterMarkerSymbol.Font = symbolFont;
            characterMarkerSymbol.Color = color;
            characterMarkerSymbol.CharacterIndex = 111;
            characterMarkerSymbol.Size = 20.0;
            IGraphicTrackerSymbol gtSymbol1 = m_graphicTracker.CreateSymbol(characterMarkerSymbol as ISymbol, null);
            m_GTSymbols.Add(0, gtSymbol1);
        }