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/* render1.h
*
* By Byron C. Darrah
* 5/13/94, Thursday
*
* render1 is a renderer which may be used with the generic vr simulator.
* The characteristics of this renderer are:
*
* - Renders polygonal objects.
* - 16 colors (this is very easily changed for the render1 module, but if you
* change it, don't forget to implement the new color scheme in the
* (system-dependent) display_list module).
* - No shading or texture mapping - polygons use flat colors.
*
* Here is a brief description of each of the functions provided to
* interface the renderer:
*
*
* o void rend_init(int *argc, char *argv[], float init_perspect);
*
* Fire up the renderer for use. Call this once at the beginning of
* your simulation, and call rend_end() once at the end. argc and argv
* are expected to be what they usually would be, as derived from the
* command line, except note that argc is a _pointer_ to an int. This
* is because rend_init() may decide to destructively remove certain
* arguments from the list. init_perspect is the focal length of the
* camera lense (note that the camera position and focus point are
* _not_ used to determine the focal length, this is). Roughly, a small
* number gives you a wide-angle-style lense, and a big value gives you
* telephoto.
*
* o void rend_end(void);
*
* Call this routine before exiting a simulation, to shut down the
* renderer and free up any resources necessary that have been allocated.
*
* o void rend_setsize(void);
*
* Synchronize the scale of drawing operations with the size of the
* actual output window.
*
* o void rend_set_camera(real_point_t *position,
* real_point_t *focus,
* real_point_t *up);
*
* This function alters the camera matrix. Note that each time the
* camera matrix is updated, all of the polygons currently submitted
* to render1 have to be retransformed and resorted, so use this function
* with care. You should never need to use this function more than
* once per frame. The focus represents a point at which the camera is
* aimed. The position is the location of the camera. up represents the
* "top" of the camera -- a vector from the postion point to the up point
* tells you which way the camera thinks is up.
*
* o void rend_register_obj(int obj_id, int npolygons);
*
* Objects call this function to register themselves with the renderer.
* Only registered objects may submit polygons. obj_id is the object's
* unique id, and npolygons is the number of polygons the object
* will use to display itself (ie: for a cube, npolygons is 6).
*
* o int rend_submit_plist(int obj_id, polygon_t *polygons);
*
* This is the function objects use to submit their polygons to render1
* for displaying. obj_id is the id of a registered object, and polygons
* is an array of polygons. It returns R1_NORMAL when successful, or
* R1_OBJ_UNKNOWN if an unregistered object id is given.
*
* o void rend_rm_plist(int obj_id);
*
* This is the function objects use to remove their polygons from the
* display. Note: this does not unregister an object, it merely
* "unsubmits" it's polygons.
*
* o void rend_transform_update_all(void);
*
* This functions performs the camera matrix transformation on all
* currently submitted polygons. It is used after rend_set_camera(),
* to update the polygons with respect to the new camera position.
* Note that polygons are automatically transformed whenever they are
* submitted. Therefore, if you can guarantee that all submitted
* polygons will be either removed or resubmitted before the next frame is
* rendered, there is no need to call this function after
* rend_set_camera().
*
* o void rend_frame(void);
*
* Actually output all currently submitted polygons to the display.
*
* o void rend_freeze(void);
*
* Pause the renderer, leaving the most recently rendered frame visible.
* Currently, this function is not guaranteed to ever return.
*/
#ifndef render1_h
#define render1_h
#define DEFAULT_PERSPECTIVE 200.0
/* Here are status codes that render1 can return */
#define R1_NORMAL 0
#define R1_OBJ_UNKNOWN 300
#define TIMEOUT 301
#define RESIZE 302
#define SELECTION 303
/*---------------------------------------------------------------------------*/
/* Here are the data structures used to interface the renderer, render1. */
/*---------------------------------------------------------------------------*/
/* Here are the colors currently supported by the renderer. It is up to
* The display_list module to actually provide these.
*/
#define BLACK 0
#define DARKRED 1
#define DARKGREEN 2
#define DARKBLUE 3
#define DARKBROWN 4
#define DARKMAGENTA 5
#define DARKCYAN 6
#define GREY1 7
#define GREY2 8
#define RED 9
#define GREEN 10
#define BLUE 11
#define BROWN 12
#define MAGENTA 13
#define CYAN 14
#define WHITE 15
typedef struct { float x, y, z;
} real_point_t;
typedef struct { float i, j, k;
} vector_t;
typedef struct { short x, y;
} int_point_t;
typedef struct plygon_struct
{
int color; /* A color table entry */
real_point_t *sim_points;
int npoints;
int_point_t *int_points;
} polygon_t;
void rend_init(int *argc, char *argv[], float init_perspect);
void rend_end(void);
void rend_setsize(void);
void rend_set_camera(real_point_t *position,
real_point_t *focus,
real_point_t *up);
void rend_register_obj(int obj_id, int npolygons);
int rend_submit_plist(int obj_id, polygon_t *polygons);
int rend_rm_plist(int obj_id);
void rend_transform_update_all(void);
void rend_frame(void);
int rend_freeze(unsigned long interval);
void rend_bell(void);
#endif /* render1_h */
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