CAGD Kit Reference

typedef struct { 
  GLdouble x, y, z;
} CAGD_POINT;

enum { 
  CAGD_SEGMENT_UNUSED = 0,
  CAGD_SEGMENT_POINT,
  CAGD_SEGMENT_TEXT,
  CAGD_SEGMENT_POLYLINE
};

enum { 
  CAGD_LBUTTONDOWN = 0,
  CAGD_LBUTTONUP,
  CAGD_MBUTTONDOWN,
  CAGD_MBUTTONUP,
  CAGD_RBUTTONDOWN,
  CAGD_RBUTTONUP,
  CAGD_MOUSEMOVE,
  CAGD_TIMER,
  CAGD_MENU,
  CAGD_LOADFILE,
  CAGD_SAVEFILE,
  CAGD_LAST
};

typedef void (*CAGD_CALLBACK)(int, int, PVOID);

enum { 
  CAGD_LOAD = WM_USER,
  CAGD_SAVE,
  CAGD_EXIT,
  CAGD_ORTHO,
  CAGD_PERSP,
  CAGD_CUE,
  CAGD_SENSLESS,
  CAGD_SENSMORE,
  CAGD_FUZZLESS,
  CAGD_FUZZMORE,
  CAGD_RESET, 
  CAGD_HELP,
  CAGD_USER 		/* use this one to create your own control */
};

void cagdBegin(PCSTR title, int width, int height);

• DESCRIPTION: This function creates drawable CAGD window and initializes all internal data structures. It should be invoked PRIOR to any cagdcall.
• PARAMETERS:
  

  title	text for window's caption;
  width	width of window in pixels (CW_DEFAULT can be used);
  height	height of window in pixels (CW_DEFAULT can be used);

• RETURN VALUE:
  None;

void cagdMainLoop();

• DESCRIPTION:
  Runs application event loop. Function exits only when user issues exit command from user interface or quit message is sent from OS or application code. You can install event callbacks that process appliaction events.
• RETURN VALUE:
  None;

• DESCRIPTION:
  Forces application to redraw its main window. Usualy used when CAGD segments where modified from the application to obtain immediate update.
• RETURN VALUE:
  None;

HWND cagdGetWindow();

• DESCRIPTION:
  Use this function to retrive valid handle of CAGD window.
• PARAMETERS:
  None;
• RETURN VALUE:
  Handle of window;

HMODULE cagdGetModule();

• DESCRIPTION:
  Use this function to retrive valid handle of application instance.
• RETURN VALUE:
  Handle of instance;

Menu and dialog functions

• DESCRIPTION:
  Append user defined menu to menu bar of window (before 'Help').
• PARAMETERS:

  hMenu	handle of menu to append;
  name	title of menu;

• RETURN VALUE:
  True if success;

• DESCRIPTION:
  Remove user defined menu from menu bar of window.
• PARAMETERS:

  hMenu

  handle of menu to remove;

• RETURN VALUE:
  True if success;

WORD cagdPostMenu(HMENU hMenu, int x, int y);

• DESCRIPTION:
  Post user defined menu at some point of window.
• PARAMETERS:

  hMenu	handle of menu to post;
  x, y	where to post the menu (window's coordinates);

• RETURN VALUE:
  ID of control that belongs to pop-up menu posted and selected.

void cagdSetHelpText(PCSTR text);

• DESCRIPTION:
  Replaces text shown in dialog window.
• PARAMETERS:

  text	text shown in help dialog.

• RETURN VALUE:
  None.

BOOL cagdShowHelp();

• DESCRIPTION:
  Popups help dialog box.
• RETURN VALUE:
  True, when dialog was successfully shown.

void cagdRotate(GLdouble angle, GLdouble x, GLdouble y, GLdouble z);

• DESCRIPTION:
  Performs a counterclockwise rotation of the coordinate system by angle degrees about the vector from the origin through the point (x, y, z).
• PARAMETERS:

  angle	the angle of rotation, in degrees.
  x, y, z	the x, y, and z coordinates of a vector, respectively.

• RETURN VALUE:
  None.

void cagdTranslate(GLdouble, GLdouble, GLdouble);

• DESCRIPTION:
  Performs a translation of the coordinate system that moves origin to the point (x, y, z).
• PARAMETERS:

  x, y, z

  the x, y, and z coordinates of a vector, respectively.

• RETURN VALUE:
  None.

void cagdScale(GLdouble, GLdouble, GLdouble);

• DESCRIPTION:
  Performs a scaling of the coordinate system.
• PARAMETERS:

  x, y, z

  the x, y, and z scale factors respectively.

• RETURN VALUE:
  None.

void cagdReset();

• DESCRIPTION:
  Restores default coordinate system.
• RETURN VALUE:
  None.

WORD cagdGetView();

• DESCRIPTION:
  Current projection view type.
• RETURN VALUE:

  CAGD_ORTHO	orthogonal projection
  CAGD_PERSP	perspective projection

void cagdSetView(WORD which);

• DESCRIPTION:
  Changes projection view to which.
• PARAMETERS:
  which is one of projection types

  CAGD_ORTHO	orthogonal projection
  CAGD_PERSP	perspective projection

• RETURN VALUE:
  None.

BOOL cagdGetDepthCue();

• DESCRIPTION:
  Current depth cue mode.
• RETURN VALUE: True when enabled, false when disabled.

void cagdSetDepthCue(BOOL enable);

• DESCRIPTION:
  Changes depth cue mode to enable.
• PARAMETERS:

  enable

  the depth cue mode enable when true.

• RETURN VALUE:
  None.

BOOL cagdToObject(int x, int y, CAGD_POINT where[2]);

• DESCRIPTION:
  Transforms window coordinates at depth 0.0 and 1.0 into object coordinates.
• PARAMETERS:

  x, y	the x, y, window coordinates respectively.
  where	the pair of object coordinates.

• RETURN VALUE:
  True when transformation can be done.

BOOL cagdToWindow(CAGD_POINT *where, int *x, int *y);

• DESCRIPTION:
  Project object coordinates into window coordinates.
• PARAMETERS:

  where	the pointer to object coordinates.
  x, y	the pointers to x, y, window coordinates respectively.

• RETURN VALUE:
  True when transformation can be done.

void cagdSetColor(BYTE r, BYTE g, BYTE b);

• DESCRIPTION:
  Sets color context for segments created after this call.
• PARAMETERS:

  r, g, b

  the RGB color.

• RETURN VALUE:
  None.

void cagdGetColor(BYTE *r, BYTE *g, BYTE *b);

• DESCRIPTION:
  Gets current color context for newly created segments.
• PARAMETERS:

  r, g, b

  the RGB color.

• RETURN VALUE:
  None.

BOOL cagdSetSegmentColor(UINT id, BYTE r, BYTE g, BYTE b);

• DESCRIPTION:
  Changes color of the id segment.
• PARAMETERS:

  id	the segment identificator.
  r, g, b	the RGB color.

• RETURN VALUE:
  True when segment exists and color can be changed.

BOOL cagdGetSegmentColor(UINT id, BYTE r*, BYTE g*, BYTE b*);

• DESCRIPTION:
  Obtains color of the id segment.
• PARAMETERS:

  id	the segment identificator.
  r, g, b	the pointers to RGB color components.

• RETURN VALUE:
  True when segment exists.

BOOL cagdShowSegment(UINT id);

• DESCRIPTION:
  Sets a state of the id segment to visible. You need to call cagdRedraw to effect the view.
• PARAMETERS:

  id	the segment identificator.

• RETURN VALUE:
  True when segment exists.

BOOL cagdHideSegment(UINT id);

• DESCRIPTION:
  Sets a state of the id segment to not visible. You need to call cagdRedraw to effect the view.
• PARAMETERS:

  id	the segment identificator.

• RETURN VALUE:
  True when segment exists.

BOOL cagdIsSegmentVisible(UINT id);

• DESCRIPTION:
  Is a state of the id segment visible?
• PARAMETERS:

  id	the segment identificator.

• RETURN VALUE:
  True when segment exists and is visible.

BOOL cagdFreeSegment(UINT id);

• DESCRIPTION:
  Destroys segment and releases resources associated with it. The segment identifier is not valid after that and may be reused. You need to call cagdRedraw to effect the view.
• PARAMETERS:

  id	the segment identificator.

• RETURN VALUE:
  True when segment exists.

void cagdFreeAllSegments();

• DESCRIPTION:
  Destroys ALL segments and releases resources associated with them. All segment identifiers is not valid after that and may be reused. You need to call cagdRedraw to effect the view.
• RETURN VALUE:
  None.

UINT cagdGetSegmentType(UINT id)

• DESCRIPTION:
  Type of existing segment or CAGD_SEGMENT_UNUSED.
• PARAMETERS:

  id	the segment identificator.

• RETURN VALUE:

  CAGD_SEGMENT_POINT

  CAGD_SEGMENT_TEXT

  CAGD_SEGMENT_POLYLINE

UINT cagdGetSegmentLength(UINT id);

• DESCRIPTION:
  Length of existing segment or zero.
• PARAMETERS:

  id	the segment identificator.

• RETURN VALUE:
  Integer segement length. Meaning depends on type:

  CAGD_SEGMENT_POINT	1 point
  CAGD_SEGMENT_TEXT	number of characters
  CAGD_SEGMENT_POLYLINE	number of verteces

BOOL cagdGetSegmentLocation(UINT id, CAGD_POINT *where);

• DESCRIPTION:
  Location of existing segment.
  NOTE: make sure to provide enough storage.
• PARAMETERS:

  id	the segment identificator.
  where	the array to store location

  Meaning of the where depends on type of the segment:

  CAGD_SEGMENT_POINT	location in object space
  CAGD_SEGMENT_TEXT	location in object space
  CAGD_SEGMENT_POLYLINE	locations of the verteces

• RETURN VALUE:
  True when existing segment location.

void cagdPick(int x, int y);

• DESCRIPTION:
  Initialize enumeration of the segments intersecting with a window location. Accuracy depends on fuzzinesse controlled from the apllication menu.
• PARAMETERS:

  x, y	the window coordinates.

• RETURN VALUE:
  None.

UINT cagdPickNext();

• DESCRIPTION:
  Next segment in enumeration initalized by cagdPick.
• RETURN VALUE:
  A segment identifier or zero when there are no more segments left to enumerate.

UINT cagdAddPoint(CAGD_POINT *where);

• DESCRIPTION:
  Creates new CAGD_SEGMENT_POINT segment at where location and sets its state as visible. Uses current color context to set segement's color. See cagdSetColor. You need to call cagdRedraw to effect the view.
• PARAMETERS:

  where

  the point location in oject space;

• RETURN VALUE:
  A segment identifier.

BOOL cagdReusePoint(UINT id, const CAGD_POINT *where);

• DESCRIPTION:
  Modifies location of the segment. You need to call cagdRedraw to effect the view.
• PARAMETERS:

  id	the segment identificator;
  where	the point location in object space;

• RETURN VALUE:
  True when existing point segment is reused.

UINT cagdAddText(const CAGD_POINT *where, PCSTR str);

• DESCRIPTION:
  Creates new CAGD_SEGMENT_TEXT segment at where location containing text str and sets its state as visible. Uses current color context to set segement's color. See cagdSetColor. You need to call cagdRedraw to effect the view.
• PARAMETERS:

  where	the text location in oject space;
  str	the text string;

• RETURN VALUE:
  A segment identifier or zero when invalid parameters.

BOOL cagdReuseText(UINT id, const CAGD_POINT *where, PCSTR str);

• DESCRIPTION:
  Modifies location and text string of the segment. You need to call cagdRedraw to effect the view.
• PARAMETERS:

  id	the segment identificator;
  where	the point location in object space;
  str	the text string;

• RETURN VALUE:
  True when existing text segment is reused.

BOOL cagdGetText(UINT id, PSTR str);

• DESCRIPTION:
  Copies text string of the segment into buffer str.
• PARAMETERS:

  id	the segment identificator;
  str	the text string storage;

• RETURN VALUE:
  True when existing text segment identifier.

UINT cagdAddPolyline(const CAGD_POINT *where, UINT length);

• DESCRIPTION:
  Creates new CAGD_SEGMENT_POLYLINE segment at where locations and sets its state as visible. Uses current color context to set segement's color. See cagdSetColor. You need to call cagdRedraw to effect the view.
• PARAMETERS:

  where	the array of verteces locations in oject space;
  length	the number of the verteces;

• RETURN VALUE:
  A segment identifier or zero when invalid parameters.

BOOL cagdReusePolyline(UINT id, const CAGD_POINT *where, UINT lenght);

• DESCRIPTION:
  Modifies the verteces of the segment. You need to call cagdRedraw to effect the view.
• PARAMETERS:

  id	the segment identificator;
  where	the array of verteces locations in oject space;
  length	the number of the verteces;

• RETURN VALUE:
  True when existing polyline segment is reused.

BOOL cagdGetVertex(UINT id, UINT index, CAGD_POINT *where);

• DESCRIPTION:
  Copies location in object space of the vertex of the polyline segment into where point.
• PARAMETERS:

  id	the segment identificator;
  index	the vertex index;
  where	the vertex location storage;

• RETURN VALUE:
  False when not existing polyline segment identifier or invalid parameters.

BOOL cagdSetVertex(UINT id, UINT index, const CAGD_POINT *where);

• DESCRIPTION:
  Modifies location in object space of the vertex of the segment. You need to call cagdRedraw to effect the view.
• PARAMETERS:

  id	the segment identificator;
  index	the vertex index;
  where	the vertex location in object space;

• RETURN VALUE:
  False when not existing polyline segment identifier or invalid parameters.

UINT cagdGetNearestVertex(UINT id, int x, int y);

• DESCRIPTION:
  Index of the vertex of the polyline segment nearest to the window location by Euclidian norm.
• PARAMETERS:

  id	the segment identificator;
  x, y	the window location coordinates;

• RETURN VALUE:
  Index of the vertex.

BOOL cagdRegisterCallback(UINT message, CAGD_CALLBACK cbf, PVOID cbdata);

• DESCRIPTION:
  Installs callback function to handle event message. If message handler has already been installed, it is replaced.
• PARAMETERS:

  id	the message identificator;
  cbf	the callback function address;
  cbdata	the argument passed to the callback function;

• RETURN VALUE:
  False when invalid parameters.