Polylines

Started by AceGIS, October 23, 2012, 12:29:07 AM

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AceGIS

Hi All,

I'm thinking I may be able to derive polylines from my models? In the snippet below I am assigning multi textures via the polygon manager. Do you think it may be possible to use modulus to create the polylines at equal intervals? Something like : if (vertextHeight.z % 10 = 0), polylineVertexs.append(vertexHeight.x, vertextHeight.y, vertexHeight.z), new Polyline(polylineVertexs) ??


for (Object3D obj : models) {
PolygonManager objPolyManager = obj.getPolygonManager();

// for each polygon set texture according to normalised vertex elevations
for (int i = 0; i < objPolyManager.getMaxPolygonID(); i++) {
float u0 = 0, u1 = 0, u2 = 0;

for (int j = 0; j < 3; j++) {
SimpleVector vertexHeight = objPolyManager.getTransformedVertex(i, j);
float normalisedHeight = (vertexHeight.z - MIN_Z)/(MAX_Z - MIN_Z);

if (j == 0) {
u0 = normalisedHeight;
}
else if (j == 1) {
u1 = normalisedHeight;
}
else if (j == 2) {
u2 = normalisedHeight;
}
}

TextureInfo ti = new TextureInfo(tm.getTextureID("esri_color_scale"), u0, u0, u1, u1, u2, u2);
objPolyManager.setPolygonTexture(i, ti);
}
world.addObject(obj);
}

EgonOlsen

I don't think that this will work very well. Apart from the fact that (vertexHeight.z % 10 = 0) almost never triggers because vertexHeight.z is a float, this will create some garbled line soup IMHO. You might want to skip that %10 condition and simply use every vertex to recreate the triangles as polylines...if that's worth it...

AceGIS

Hi Egon,

No. I'm not trying to create the polygons triangle boundary polylines but rather contour lines. What if I use the transformed vertex height before normalising? Convert the value to an int, then mod 10 = 0?

OR is it possible to have a texture with transparent pixels? Then I could use the transparent pixel for no display and the color pixel for the contour line?

OR any other suggestions?