gdraw.h

The <gdraw.h> Header File

Routines for graph screen drawing

Note: This header file is prepared for use, but not documented yet. These functions are still useless without support of some other functions which are not properly defined yet, so I didn't document this header file.

Functions

GD_Circle
GD_Contour
GD_Eraser
GD_HVLine
GD_Line
GD_Pen
GD_Select
GD_Text
GR3_paint3d: Draws the current 3D graph.
GR3_xyToWindow: Converts 3D coordinates to window coordinates.
GZ_Box: This function performs the Zoom Box command.
GZ_Center: Changes the zoom settings of the graph.

Predefined Types

GraphModes: Describes different graphing modes.

GD_Circle

void GD_Circle (void);

GD_Contour

void GD_Contour (void);

GD_Eraser

void GD_Eraser (void);

GD_HVLine

void GD_HVLine (short Orientation);

GD_Line

void GD_Line (void);

GD_Pen

void GD_Pen (void);

GD_Select

void GD_Select (void);

GD_Text

void GD_Text (void);

GR3_paint3d

void GR3_paint3d (void);

Draws the current 3D graph.

GR3_paint3d draws the currently active 3D graph using the current mode, format, and zoom settings. If the graph is not already calculated, it will display the calculation status.

Note: the graph application should be active when this function is executed. You can do this by executing:

EV_startApp (EV_getAppID ("TIGRAPH"), AP_START_CURRENT);

GR3_xyToWindow

void GR3_xyToWindow (float xc, float yc, float* zc, short *WinX, short *WinY);

Converts 3D coordinates to window coordinates.

GR3_xyToWindow takes the 3D-graph point (xc,yc) and determines:

the Z-coordinate (zc) at the point;
the (WinX,WinY) pair of window coordinates for the location of this point on the 3D graph currently displayed.

GZ_Box

void GZ_Box (void);

This function performs the Zoom Box command.

This is the equivalent of the Zoom Box command. After a keypress, it will display the graph screen. If there is none (i.e. no function graphed), and there aren't any graphs selected, then you will be presented with a blank screen. If there is a function (or more) selected, then it will present you with a "dummy axis" (a smaller one).

GZ_Center

void GZ_Center (void);

Changes the zoom settings of the graph.

This function basically changes the zoom settings of the graph. The first time the function is called, it changes the graph to the standard settings. The next time it is called, if there is a function selected, it increases xmin and xmax by 10, and increases ymin and ymax also. If there is no function selected, it remains at the standard. It seems that this function has some internal values for xmin and xmax, and any changes are ignored, meaning that, if you call it twice and change the values for xmin and xmax, and call this function a third time, the changes you made will be ignored.

GraphModes

enum GraphModes {GR_FUNC = 1, GR_PAR = 2, GR_POL = 3, GR_SEQ = 4, GR_3D = 5, GR_DE = 6};

Describes different graphing modes.

This is an enumeration describing the modes of the Graph screen. It is currently used in CheckReservedName and CheckSysFunc from vat.h and also in GR_WIN_VARS from graphing.h.

The meaning of the different flags is given in the description of GR_WIN_VARS.