CHAPTER 10: SPECIAL DRAWING FUNCTIONS
 ARCTANGENT() Returns the angle from the current point to another.
 CAP_MOVE()   Moves the current active point to a new location.
 CLS_SCREEN() Clears the graphics screen to a background color or other color.
 COSINE()     Finds the cosine of an angle.
 FBOX()       Draws a box between two points.
 FCIRCLE()    Draws a circle with a given center and radius.
 FCIRCL_ARC() Draws a circular arc with a given center and radius.
 FCIRC_CLOS() Draws a closed circular arc with given center and radius.
 FCOLOR()     Sets the background color for CGA 4-color mode.
 FDRAW()      Draws complex figures from a format string.
 FILLAREA()   Fills an area on the screen with color and an optional pattern.
 FLINE()      Draws a line between two points.
 FOVAL()      Draws an ellipse with a given center and radius.
 FOVAL_ARC()  Draws an elliptical arc with given center and radius.
 FOVAL_CLOS() Draws a closed elliptical arc with given center and radius.
 FPIE()       Draws a pie slice.
 FPOINT()     Returns the pixel's color at the specified absolute coordinates.
 FPOLY_LINE() Draws a series of line segments.
 FPSET()      Places a color dot on the screen at position X,Y.
 FSCREEN()    Changes to the graphics screen.
 GET_CURSOR() Sets the cursor on or off for GET_GET().
     GET_COL()    Returns the current horizontal cursor position.
     GET_ROW()    Returns the current vertical cursor position.
 GET_GET()    Gets an input string from the user.
 GET_GETCLR() Sets the colors for GET_SAY() and GET_GET().
 GET_SAY()    Prints text on the screen similar to the Clipper SAY function.
 IS_CURSOR()  Checks to see if the cursor is on or off.
 PAINTAREA()  Fills a complex shape on the screen with a solid color.
 PAT_EDFILL() Modifies the pre-defined fill patterns.
 PAT_SETFIL() Selects a pattern to be used with filled figures.
 PAT_SETLIN() Selects a pattern to be used by line drawing functions.
 PLINE()      Draws a line in a direction and distance.
 SET_DITHER() Sets the translation between colors and dither patterns.
 SET_XOR()    Toggles line drawing to be XORed to the background.
 SINE()       Finds the sine of an angle.
                    CHAPTER 11: VIEWPORT & SCALING FUNCTIONS
 ABS_TO_X()   Returns the X value of the logical pixel position on screen.
 ABS_TO_Y()   Returns Y value of logical pixel position on screen.
 ATX()        Returns the physical pixel or logical X position on screen.
 ATY()        Returns physical pixel or logical Y position on screen.
 IN_VIEW()    Returns whether a point is in the viewport.
 SET_WORLD()  Sets the scaling factor, origin and direction of the axes.
     WLD_XORG()   Returns the X origin.
     WLD_YORG()   Returns the Y origin.
     WLD_XSCALE() Returns the X scale.
     WLD_YSCALE() Returns the Y scale.
     WLD_XDIR()   Returns the X scale direction.
     WLD_YDIR()   Returns the Y scale direction.
 VIEW_CLOSE() Closes the viewport with the view handle parameter.
 VIEW_CURR()  Returns the current viewport number.
 VIEW_OPEN()  Opens a new viewport and returns the viewport's handle.
     VIEW_WIDE()  Returns the width in pixels of the current viewport.
     VIEW_HIGH()  Returns the height in pixels of the current viewport.
     VIEW_XMIN()  Returns the left absolute pixel position of current viewport.
     VIEW_YMIN()  Returns the top absolute pixel position of current viewport.
 VIEW_SWAP()  Changes from the current viewport to another.
 VW_FLCLOSE() Deletes files opened with VW_FLOPEN() from your disk.
 VW_FLOPEN()  Opens disk file to hold video data underlying viewports.
                           CHAPTER 12: USING A MOUSE
 CUR_DEFINE() Redefines the mouse cursor to a custom design.
 FLUSH_EVQ()  Flushes the event queue.
 IS_POS_REL() Determines if the current reference positioning is relative.
 KEY_MACRO()  Passes a string of ASCII characters to KEY_PRESS().
 KEY_PRESS()  Waits for an event to occur.
     KP_ABS_X()   Returns the absolute horizontal mouse position.
     KP_ABS_Y()   Returns the absolute vertical mouse position.
     KP_SCALE_X() Returns the world scale horizontal mouse position.
     KP_SCALE_Y() Returns the world scale vertical mouse position.
     KP_MSTATE()  Returns the mouse state.
     KP_BUTTON()  Returns whether the mouse buttons were pressed.
     KP_SCAN()    Returns the keyboard scan code.
     KP_ASCII()   Returns the ASCII value of the key pressed.
     KP_FLAGS()   Holds the keyboard's shift status flags.
     KP_MENU()    Returns the last menu set selected.
     KP_ITEM_NO() Returns the menu button number selected.
     KP_TIME()    Returns the low word of the IBM clock time.
 MS_BUTTON()  Indicates the currently pressed mouse buttons.
 MS_CUROFF()  Turns the mouse cursor off.
 MS_CURON()   Turns the mouse cursor on.
 MS_CURR_X()  Returns the absolute horizontal mouse position.
 MS_CURR_Y()  Returns the absolute vertical mouse position.
 MS_CURSOR()  Sets the mouse cursor pattern.
 MS_HALT()    Stops mouse interrupt checking.
 MS_MASK()    Sets the call mask for mouse subroutines.
 MS_MICKEY()  Checks if the mouse moved since the last call to MS_MICKEY().
 MS_MSTATE()  Checks the current mouse button status.
 MS_REGION()  Returns the region that the mouse was in.
 MS_REPEAT()  Specifies parameters for repeating if the button is held down.
 MS_RESET()   Returns the number of buttons on the mouse.
 MS_SETXY()   Moves the mouse cursor to the specified coordinates.
 MS_WINDOW()  Restricts the mouse cursor to specified area.
 POS_ABS()    Sets the relative positioning to return absolute values.
 POS_ATTR()   Defines attributes and position for the mouse display.
 POS_COLOR()  Defines the color for the mouse position display.
 POS_ONOFF()  Turns the mouse positioning on or off for a specified region.
 POS_REFER()  Defines base coordinates to offset mouse reference positioning.
 POS_SIZE()   Defines width and decimal length for mouse positioning display.
 REGN_INIT()  Sets up new mouse regions.
 REGN_OFF()   Turns all regions off, and the mouse reverts to the base region.
 REGN_ON()    Turns regions back on after a previous call to REGN_OFF().
 REGN_SET()   Defines attributes for specified region.
 RET_TIME()   Returns the lower 2 bytes of the BIOS time.
 TAB_MODE()   Toggles between relative and absolute coordinate systems.
 TAB_RESIZE() Sets the active region on the SummaGraphics tablet.
 TIME_SET()   Specifies the number of clock ticks before a timer event.
 TIME_START() Restarts the timer after a call to TIME_STOP().
 TIME_STOP()  Suspends timer event checking.
                          CHAPTER 13: MENUS & BUTTONS
 BUTTON_ADD() Adds an area to the menu as a button.
 BUTTON_CNT() Returns the number of buttons defined in a specified menu.
 BUTTON_CUR() Returns the last button selected from a menu.
 BUTTON_EDT() Modifies a button on the specified menu.
 BUTTON_HOT() Determines if the coordinates fall within the defined button.
 CLR_ALL()    Clears all menus from memory.
 CLR_BUTTON() Clears a button from the specified menu.
 CLR_MENU()   Clears a menu from memory.
 IS_MENU_ON() Determines if the specified menu is awake or asleep.
 MENU_COLOR() Sets the color attributes for all menu systems.
 MENU_EDIT()  Modifies the attributes of a menu.
 MENU_ITEM()  Adds a text button to a menu.
 MENU_ONLY()  Opens up a menu exclusively.
 MENU_OPEN()  Opens and defines attributes for a new menu.
 MENU_SLEEP() Puts the specified menu to sleep.
 MENU_WAKE()  Wakes up a menu that was previously put to sleep.
 SCRL_CLOSE() Closes a scroll bar you have opened.
 SCRL_HOT()   Checks if the mouse has touched the scroll bar.
 SCRL_OPEN()  Sets up a scroll bar.
 SCRL_SET()   Sets the indicator on a scroll bar.
 SCRL_SIZE()   Sets display options for a scroll bar.
 SCRL_SLEEP() Makes a scroll bar inactive to the mouse.
 SCRL_WAKE()  Makes a scroll bar active to the mouse.
                            CHAPTER 14: CAD FUNTIONS
 CAD_SETUP()  Changes the defaults in the CAD system.
 CHECK_OLAP() Checks for overlapping objects.
 CIRCLE_3PT() Converts an array of 3 points to a circle for OBJ_ADD().
 ENTER_PNT()  Allows the user to enter the exact point when drawing objects.
     ENTER_FLAG() Sets flag for object drawing options.
     ENTER_TYPE() Returns the current type of object you are drawing.
 GRID_PNT()   Moves the mouse cursor to the closest grid point.
 GRID_SET()   Sets the status and size of the grid system.
 HOT_INFO()   Returns information from the hot object buffer.
 HOT_METHOD() Changes the search method of current hot object.
 HOT_VIEW()   Sets which viewport will have movable objects.
 LAYER_CLOS() Closes an open layer, deleting all objects associated with it.
 LAYER_CNT()  Returns the number of objects on the specified layer.
 LAYER_CURR() Returns the current layer or sets a new current layer.
 LAYER_INFO() Stores descriptions from all objects in a layer into an array.
 LAYER_NUM()  Returns the number of layers defined.
 LAYER_ON()   Changes a layer's status for object searches and remapping.
 LAYER_OPEN() Opens the next available layer.
 LINE_BREAK() Breaks a line of a box or polyfigure.
 MARK_BREAK() Breaks marked object groups into individual objects.
 MARK_COMB()  Combines all marked objects into one object group.
 MARK_WIND()  Marks or unmarks all objects within a defined window.
 MOV_TO_PNT() Moves the mouse cursor to a specified world coordinate.
 MS_OBJECT()  Draws an object on the drawing surface with the mouse.
 MS_POINTS()  Draws a line freehand.
 OBJ_ADD()    Adds an object to a drawing under program control.
 OBJ_ARRSIZ() Returns the size of the array needed for OBJ_GETPNT().
 OBJ_COPY()   Makes a copy of a specified object from any layer.
 OBJ_DELETE() Deletes selected objects.
 OBJ_EDIT()   Edits the attributes for selected objects.
 OBJ_FIND()   Finds an object in a layer and makes it hot.
 OBJ_GETPNT() Retrieves information about a hot object into a Clipper array.
 OBJ_HOT()    Finds the closest object and makes it 'hot'.
 OBJ_HOTPNT() Finds the closest object's nearest point and makes it 'hot'.
 OBJ_MIRROR() Reflects an object.
 OBJ_MOVE()   Moves the specified object with mouse control.
 OBJ_MOVPNT() Moves the nearest point of an object with mouse control.
 OBJ_ROTATE() Rotates an object.
 OBJ_SCALE()  Changes the size of an object.
 OBJ_SETPNT() Changes a value in the array returned by OBJ_GETPNT().
 OBJ_SHEAR()  Distorts the shape of an object.
 OBJ_SNAP()   Moves an object guided by a line to a new position.
 OBJ_SNAPNT() Moves a point guided by a line to a new position.
 OBJ_TO_LAY() Copies an object from one layer to another.
 OBJS_MAP()   Redraws the view from the object stacks.
 OBJS_READ()  Restores objects previously saved to a DOS file.
 OBJS_SAVE()  Saves objects to a DOS file.
 RC_POS()     Returns the position for fixed-space text.
 RET_END_X()  Returns the ending X world coordinate from previous MS_OBJECT().
 RET_END_Y()  Returns the ending Y world coordinate from previous MS_OBJECT().
 RET_RADIUS() Returns the radius from the previous MS_OBJECT().
 RET_STR_X()  Returns starting X world coordinate from previous MS_OBJECT().
 RET_STR_Y()  Returns starting Y world coordinate from previous MS_OBJECT().
 SCAN_CONV()  Converts key numbers to scan codes for use with CAD_SETUP().
 WIND_BREAK() Breaks all objects combined at a specified level.
 WIND_COMB()  Combines objects marked by a window.