Global C Variables
Global TCL Variables (below)

Many of the C global variables are linked to TCL global variables ( More about Variable Linking))

Data Sets

• IPlotData..............Pointer to current data set
• IPlotDataSets.......Array of all data sets

More About Data Sets

Transformation Parameters

• min_x, max_x...........the extent of the current data set in
• min_y, max_y...........data coordinates
• x_scale, y_scale.........scale values for converting to screen coords
• x_trans, y_trans.........x and y translation for converting to screen coords

The min and max extent variables are not to be confused with those in the Misc category of the IPlot Data Set Object See More About Data Sets These extent variables are set equal to the data set extent variables upon opening a new data set. However, when the user zoom's in on a data set, it is these variables that get reset to hold the current minimum and maximum values that are being displayed. ( More about Zooming)

The scale and trans variables hold the parameters necessary to transform the data coordinates into the screen coordinates at the current zoom level which is effectively defined by the extent variables above. ( More about Zooming)

Grid Spacing

• current_gridsize_x...........size of the superimposed grid lines in
• current_gridsize_y............screen coords (nothing to do with mesh)

These variables hold the current value of the spacing interval between the grid lines which can be plotted over the canvas, and the grid values which are displayed along the axes. Whenever a change is made in the current working data set, these values are stored in similar variables in the IPlot Data Set's Miscellaneous Category.

Labels

• current_title_space................ space for the local title
• current_xaxis_space.............. space for the local x-axis label
• current_yaxis_space.............. space for the local y-axis label
• current_title...................... pointer to the local title
• current_xaxis.................... pointer to the local x-axis label
• current_yaxis.................... pointer to the local y-axis label

These were done with seperate array and pointers because I had a lot of trouble linking a C string variable to a TCL variable and this seemed to be the best way to do it. ( Linking C and TCL Variables)

These variables hold the current value of the title and axis labels. Whenever a change is made in the current working data set, these values are stored in similar variables in the IPlot Data Set's Miscellaneous Category.

Plotting Parameters

• plot_geom
• plot_mesh
• plot_contour
• plot_node
• plot_1d

These variables are flags that tell the plotting function which properties of the data set should be plotted. The Plotting parameters have three states.

• -1 Do Not Plot
• 0 Already Plotted
• 1 Need to Plot

These variables hold the current value of the flags. Whenever a change is made in the current working data set, these values are stored in similar variables in the IPlot Data Set's Miscellaneous Category.

Miscellaneous

• noof_data_sets...................Number of data sets currently defined
• current_noof_regions........Number of regions in current data set
• color_mode...................... 16 color mode or black and white
• current_dimen.................. Is the current data set 1D or 2D
• scale_type......................... 0 = Linear 1 = Log10

Names

• color
• pattern
• material

These hold a list of colors, patterns and material names used.

Global TCL Variables

Many of the TCL global variables are linked to C global variables ( More about Variable Linking)) All TCL global variables have the prefix ipl_ so that they won't interfere with other TCL applications that may be running.

Plot Parameters

• ipl_plotmesh
• ipl_plotgeom
• ipl_plotcontour
• ipl_plotnode
• ipl_plot1d

These variables are all linked to the similarly named variables described above.

Transformation Parameters

• ipl_min_x, ipl_min_y
• ipl_max_x, ipl_max_y
• ipl_scale_x, ipl_scale_y
• ipl_trans_x, ipl_trans_y

These variables are all linked to the similarly named variables described above.

Dialog Information Passers

• ipl_tmp_name, ipl_old_name
• ipl_tmp_color, ipl_old_color
• ipl_tmp_min, ipl_old_min
• ipl_tmp_label, ipl_old_label
• ipl_tmp_incr, ipl_old_incr
• ipl_tmp_num, ipl_old_num
• ipl_tmp_noof, ipl_old_noof
• ipl_tmp_contour, ipl_old_contour
• ipl_tmp_color, ipl_old_color
• ipl_tmp_value, ipl_old_value

These variables are used in various dialogs to pass information back and forth from TCL code to C code. the ipl_old variables are used so that if the user presses cancel in a dialog, all of the information can be reset. The ipl_tmp variables are used to pass the values that will be changed if the user presses Ok

Labels

• ipl_toplabel........................ Title
• ipl_leftlabel....................... Y-Axis
• ipl_bottomlabel................. X-Axis
• ipl_showgl......................... Display or hide Grid Lines
• ipl_showgv........................ Display or hide Grid Values
• ipl_regionlegend............... Display or hide Region Legend
• ipl_contourlegend............. Display or hide Contour Legend

The label variables are linked to the title and axis variables defined above in the C global variables section.

The other variables are simply flags that indicate whether or not the various artifacts should be displayed.

Mouse Selection (Zoom and Cross Section)

• ipl_buttonhold............... Is Mouse Button 1 being held down?
• ipl_ZP1x ipl_ZP1y........ Zoom Point 1 x and y coordinates
• ipl_ZP2x ipl_ZP2y........ Zoom Point 2 x and y coordinates
• ipl_CSx.......................... cross section x-coord - screen coordinates
• ipl_RCSx....................... cross section x-coord - data set coordinates
• ipl_doingCS.................. Are we currently defining a Cross Section
• ipl_fullzoomout............ Are we going to full zoom out

These variables are used in the selection of a Zoom Area ( More about Zooming) and in the selection of a 1D Cross Section ( More about 1D Cross Sections)

Miscellaneous

• ipl_noofregions................ Linked to current_noof_regions above
• ipl_canvas_width............. matches (not linked) PLOT_WIDTH in plot.h
• ipl_canvas_height............ matches (not linked) PLOT_HEIGHT in plot.h
• ipl_colormode.................. Linked to color_mode above
• ipl_datasetactive.............. Is there an active data set?
• ipl_scaletype.................... Linked to scale_type above
• ipl_filename.................... Name of file to open
• ipl_contoursdefd.............. Number of contours defined
• ipl_noofdatasets............... Number of data sets defined

IPlot Home Page Technical Doc's User's Guide