Source Code

'~ This is file example_curve_areas.bas
'~ Example source code for GooData graphic library.
'
'~ Licence: GPLv3
'~ (C) 2012 Thomas[ dot ]Freiherr[ at ]gmx[ dot ]net


CONST cols = 2, az = 30, l = 4 * ATN(1), line_group = 2.0
DIM AS GooType datas(az, cols)
FOR i AS INTEGER = 0 TO az
  VAR x = -l + i / az * 2 * l
  datas(i, 0) = x
  datas(i, 1) = SIN(x)
  datas(i, 2) = SIN(x) ^ 3
NEXT
VAR Dat = goo_data_points_new(az + 1, cols + 1, @datas(0, 0))
VAR wdth = 422.0, hght = 240.0

VAR group = goo_canvas_group_new(Glob, _
            "line_width", 2.0, _
            "font", "Arial", _
            NULL)

VAR title = goo_canvas_text_new(group, _
            "<span size=""xx-large"">"_
            "Areas in a Grid Box" _
           !"</span>\n", _
            0.0, 0.0, wdth, GOO_CANVAS_ANCHOR_SW, _
            "use_markup", TRUE, _
            "alignment", PANGO_ALIGN_CENTER, _
            NULL)

VAR grid = goo_canvas_rect_new(group, _
            0.0, 0.0, wdth, hght, _
            NULL)

VAR xaxis = goo_axis_new(group, grid, GOO_GRIDAXIS_SOUTH, _
            "angle <i>φ</i>", _
            "range", "-3.3 3.3", _
            "ticks", "1", _
            NULL)

goo_axis_set_grid_properties(xaxis, _
            "stroke_color", "lightgray", _
            NULL)

VAR yaxis = goo_axis_new(group, grid, GOO_GRIDAXIS_WEST, _
           !"sin(<i>φ</i>)\ncos(<i>φ</i>)", _
            "offset_label", 7., _
            "range", "-1.15 1.15", _
            "ticks", ".5", _
            NULL)

goo_axis_set_grid_properties(yaxis, _
            "stroke_color", "lightgray", _
            NULL)

VAR curve1 = goo_curve2d_new(group, xaxis, yaxis, Dat, _
            "channels", "0 2", _
            "line-type", "none", _
            "stroke_color", "green", _
            "area-direction", "north", _
            "area_linetype", "bezier 0.6", _
            NULL)

goo_curve2d_set_area_properties(curve1, _
            "fill-color-rgba", &h00C00030, _
            NULL)

VAR curve2 = goo_curve2d_new(group, xaxis, yaxis, Dat, _
            "channels", "0 1", _
            "fill_color", "lightred", _
            "line_type", "none", _
_            "stroke_color", "red", _
_            "area", "Y0", _
            "area_linetype", "bezier 0.6", _
            "area_direction", "y0.41", _
            NULL)

goo_curve2d_set_area_properties(curve2, _
            "fill-color-rgba", &hC0000030, _
            NULL)