Drawing

The Drawing component provides functionality for rendering graphics in the X-Plane environment. Currently, this includes writing a single text string on the screen, and rendering a sequence of waypoints in the X-Plane world.

###Types

####Waypoint A data struct containing a latitude, longitude, and altitude.

####Localpoint A data struct containing an OpenGL local X, Y, Z coordinate.

####Drawing Contains methods to manipulate what X-Plane Connect draws to the screen.

#####Drawing Methods

######ClearMessage Signature: static void ClearMessage();

Clears the current message on the screen if any and unregisters the draw callback for message drawing.

######SetMessage Signature: static void SetMessage(int x, int y, char* msg);

Sets a string to be drawn at a particular point on the screen. For simplicity of implementation, the (x, y) coordinate specified is the bottom left point of the first line of the message.

######AddWaypoints Signature: static void AddWaypoints(Waypoint points[], size_t numPoints);

Adds a set of waypoints to the list of waypoints to be drawn.

######ClearWaypoints Signature: static void ClearWaypoints();

Clears the set of waypoints that are drawn.

######RemoveWaypoints Signature: static void RemoveWaypoints(Waypoint points[], size_t numPoints);

Removes a set of waypoints to the list of waypoints to be drawn.

###Internal Functions

####cmp Signature: static int cmp(const void * a, const void * b)

A simple comparison function for std::size_t needed for qsort.

####gl_DrawCube Signature: static void gl_drawCube(float x, float y, float z, float d)

Draws a cube centered at the given coordinate, which is d meters away from the player aircraft. The distance is used to scale the cubes so that they appear to be approximately the same size on the screen.

####MessageDrawCallback Signature:

static int MessageDrawCallback(XPLMDrawingPhase inPhase,
                               int inIsBefore,
                               void * inRefcon)

Callback for performing the drawing of the string specified by SetMessage.

####RouteDrawCallback Signature:

static int RouteDrawCallback(XPLMDrawingPhase inPhase,
                             int inIsBefore,
                             void * inRefcon)

Callback for performing the drawing waypoints.