[vtkusers] Colour a triangle

[Naoko TAKAYA]

Dear VTK-users,

I have a simple problem.
I just want to colour the triangle with specified
rgb values specified at each vertices.

It only gets coloured in blue and red and nothing else.
My brief code is the following. Please tell me what I'm doing wrong...

Any advice is very much appreciated ;-)

Naoko.

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	float points[3][3];
	int pts[3] = {0,1,2};
	int i;
	float x1, y1, z1, x2, y2, z2, x3, y3, z3;
	int NumOfPoints = 0;
	int PointOfTriangle[3];

// Coordinates of triangle vertices
	x1=0.0f; y1=0.0f; z1=0.0f;
	x2=2.0f; y2=2.0f; z2=0.0f;
	x3=4.0f; y3=0.0f; z3=0.0f;

	points[0][0] = x1;
	points[0][1] = y1;
	points[0][2] = z1;
	points[1][0] = x2;
	points[1][1] = y2;
	points[1][2] = z2;
	points[2][0] = x3;
	points[2][1] = y3;
	points[2][2] = z3;

	vtkFloatArray *vScalars = vtkFloatArray::New();
    vScalars -> SetNumberOfComponents(3);
    vScalars -> SetNumberOfTuples(3);
	vtkPoints *vPts = vtkPoints::New();
	vPts -> SetDataTypeToFloat();
	vtkCellArray *vCellArray = vtkCellArray::New();

// Insert triangle vertices
	for(i=0; i<3; i++){
		vPts -> InsertPoint(i, points[i]);	
	}

	PointOfTriangle[0] = NumOfPoints;
	PointOfTriangle[1] = NumOfPoints + 1;
	PointOfTriangle[2] = NumOfPoints + 2;

	vCellArray -> InsertNextCell(3, PointOfTriangle);

// Specify RGB values at each vertice of the triangle
	vScalars -> SetComponent( 0, 0, 255 );
	vScalars -> SetComponent( 0, 1, 0 );
	vScalars -> SetComponent( 0, 2, 0 );
	vScalars -> SetComponent( 1, 0, 0 );
	vScalars -> SetComponent( 1, 1, 255 );
	vScalars -> SetComponent( 1, 2, 0 );
	vScalars -> SetComponent( 2, 0, 0 );
	vScalars -> SetComponent( 2, 1, 0 );
	vScalars -> SetComponent( 2, 2, 255 );

	vtkPolyData *vData = vtkPolyData::New();
	vData -> SetPoints(vPts);
	vData -> SetPolys(vCellArray);
	vData -> GetPointData() -> SetScalars(vScalars);
	vData -> Squeeze();

	// mapper
	vtkPolyDataMapper *vMapper = vtkPolyDataMapper::New();
	vMapper -> ImmediateModeRenderingOn();
	vMapper -> ScalarVisibilityOn();
	vMapper -> SetInput(vData);
	vMapper -> Update();
	// property
	vtkProperty *vProp = vtkProperty::New();
	vProp -> SetInterpolationToGouraud();
	vProp -> SetOpacity(0.8f);
	// actor
	vtkActor *vActor = vtkActor::New();
	vActor -> SetMapper(vMapper);
	vActor -> SetProperty(vProp);
	// render
	vRenderer -> AddActor(vActor);

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