Surface Shading

pythondemo\surfaceshading.py
#!/usr/bin/python

# The ChartDirector for Python module is assumed to be in "../lib"
import sys, os
sys.path.insert(0, os.path.join(os.path.abspath(sys.path[0]), "..", "lib"))

from pychartdir import *
import math

def createChart(chartIndex) :

    # The x and y coordinates of the grid
    dataX = [-10, -8, -6, -4, -2, 0, 2, 4, 6, 8, 10]
    dataY = [-10, -8, -6, -4, -2, 0, 2, 4, 6, 8, 10]

    # The values at the grid points. In this example, we will compute the values using the formula z
    # = x * sin(y) + y * sin(x).
    dataZ = [0] * (len(dataX) * len(dataY))
    for yIndex in range(0, len(dataY)) :
        y = dataY[yIndex]
        for xIndex in range(0, len(dataX)) :
            x = dataX[xIndex]
            dataZ[yIndex * len(dataX) + xIndex] = x * math.sin(y) + y * math.sin(x)

    # Create a SurfaceChart object of size 380 x 400 pixels, with white (ffffff) background and grey
    # (888888) border.
    c = SurfaceChart(380, 400, 0xffffff, 0x888888)

    # Demonstrate various shading methods
    if chartIndex == 0 :
        c.addTitle("11 x 11 Data Points\nSmooth Shading")
    elif chartIndex == 1 :
        c.addTitle("11 x 11 Points - Spline Fitted to 50 x 50\nSmooth Shading")
        c.setInterpolation(50, 50)
    elif chartIndex == 2 :
        c.addTitle("11 x 11 Data Points\nRectangular Shading")
        c.setShadingMode(RectangularShading)
    else :
        c.addTitle("11 x 11 Data Points\nTriangular Shading")
        c.setShadingMode(TriangularShading)

    # Set the center of the plot region at (175, 200), and set width x depth x height to 200 x 200 x
    # 160 pixels
    c.setPlotRegion(175, 200, 200, 200, 160)

    # Set the plot region wall thichness to 5 pixels
    c.setWallThickness(5)

    # Set the elevation and rotation angles to 45 and 60 degrees
    c.setViewAngle(45, 60)

    # Set the perspective level to 35
    c.setPerspective(35)

    # Set the data to use to plot the chart
    c.setData(dataX, dataY, dataZ)

    # Set contour lines to semi-transparent black (c0000000)
    c.setContourColor(0xc0000000)

    # Output the chart
    c.makeChart("surfaceshading%s.jpg" % chartIndex)


createChart(0)
createChart(1)
createChart(2)
createChart(3)