protected void SetAlpha(SceneObjectPart part, double alpha, int face)
{
if (part == null || part.ParentGroup == null || part.ParentGroup.IsDeleted)
return;
Primitive.TextureEntry tex = part.Shape.Textures;
Color4 texcolor;
if (face >= 0 && face < GetNumberOfSides(part))
{
texcolor = tex.CreateFace((uint)face).RGBA;
texcolor.A = Util.Clip((float)alpha, 0.0f, 1.0f);
tex.FaceTextures[face].RGBA = texcolor;
part.UpdateTextureEntry(tex.GetBytes());
return;
}
else if (face == ScriptBaseClass.ALL_SIDES)
{
for (int i = 0; i < GetNumberOfSides(part); i++)
{
if (tex.FaceTextures[i] != null)
{
texcolor = tex.FaceTextures[i].RGBA;
texcolor.A = Util.Clip((float)alpha, 0.0f, 1.0f);
tex.FaceTextures[i].RGBA = texcolor;
}
}
// In some cases, the default texture can be null, eg when every face
// has a unique texture
if (tex.DefaultTexture != null)
{
texcolor = tex.DefaultTexture.RGBA;
texcolor.A = Util.Clip((float)alpha, 0.0f, 1.0f);
tex.DefaultTexture.RGBA = texcolor;
}
part.UpdateTextureEntry(tex.GetBytes());
return;
}
}