SYNOPSIS
#include <agar/core.h> #include <agar/gui.h> #include <agar/map/rg.h>
DESCRIPTION
The
RG_Feature element performs some operation on the surface of a
RG_Tile(3). For example, a
Blur filter may be implemented as a
RG_Feature. The interface is defined by the
RG_FeatureOps structure:
The init(), load(), save(), destroy() and edit() operations are analogous to the AG_Object(3) operations of the same name. init() must invoke RG_FeatureInit().
The menu() and toolbar() operations, where not NULL, generate and return AG_Menu(3) items and an AG_Toolbar(3), respectively, for the GUI.
The apply() operation performs the actual modification on the tile. The x and y arguments are specific to the instance of this feature and may be ignored.
typedef struct rg_feature_ops {
const char *type; /* Feature name */
AG_Size len; /* Size of structure */
const char *desc; /* Feature description */
int flags;
#define RG_FEATURE_AUTOREDRAW 0x01 /* Automatic redraw on edit */
void (*init)(void *self, RG_Tileset *set, int flags);
int (*load)(void *self, AG_DataSource *ds);
void (*save)(void *self, AG_DataSource *ds);
void (*destroy)(void *self);
void (*apply)(void *self, RG_Tile *tile, int x, int y);
void (*menu)(void *self, AG_MenuItem *menu);
AG_Toolbar *(*toolbar)(void *self, RG_Tileview *view);
AG_Window *(*edit)(void *self, RG_Tileview *view);
}
The init(), load(), save(), destroy() and edit() operations are analogous to the AG_Object(3) operations of the same name. init() must invoke RG_FeatureInit().
The menu() and toolbar() operations, where not NULL, generate and return AG_Menu(3) items and an AG_Toolbar(3), respectively, for the GUI.
The apply() operation performs the actual modification on the tile. The x and y arguments are specific to the instance of this feature and may be ignored.
INTERFACE
void RG_FeatureInit (void *feature, RG_Tileset *ts, int flags, const RG_FeatureOps *featureOps)
void RG_FeatureAddPixmap (RG_Feature *feature, RG_Pixmap *pixmap)
void RG_FeatureAddSketch (RG_Feature *feature, RG_Sketch *sketch)
void RG_FeatureDelPixmap (RG_Feature *feature, RG_Pixmap *pixmap)
void RG_FeatureDelSketch (RG_Feature *feature, RG_Sketch *sketch)
The RG_FeatureInit() function initializes a derivate of the RG_Feature structure, described by the ops structure (see DESCRIPTION section). The following flags are defined:
| RG_FEATURE_AUTOREDRAW | Periodically redraw target tile when feature is undergoing edition. |
Features occasionally need to reference other resources in the current RG_Tileset. The RG_FeatureAddPixmap() and RG_FeatureAddSketch() functions add a reference to a pixmap or sketch, respectively. RG_FeatureDelPixmap() and RG_FeatureDelSketch() remove the given reference.
