MadButterfly: src/redraw_man.c comparison

comparison src/redraw_man.c @ 519:7a1b17ebb3b4 Android_Skia

Change documentation for zeroing

author	Thinker K.F. Li <thinker@branda.to>
date	Thu, 17 Dec 2009 16:09:46 +0800
parents	d186d1e24458
children	f106b57b8660

comparison

equal deleted inserted replaced

-:3a7bce43ec6e
+:7a1b17ebb3b4
 * Separated lists should be maintained for each cached coord and it's
 * descendants.
 *
 * \section cache_imp Implementation of Cache
 * Both cached coords and coords that opacity != 1 need a canvas to
-* draw descendants on.  Both cases are traded in the same way.
+* draw descendants on.  Both cases are traded in the same way.  Every
-* Every of them own a canvas_info to describe canvas and related
+* of them own a canvas_info to describe canvas and related
 * information.  aggr_matrix of descendants must be adjusted to make
-* left-top of range just at origin of canvas.  It can save space by setting
+* left-top of bounding box just at origin (0, 0) of canvas.  It saves
-* just large enough to hold rendering result of descendants.  The process
+* space to give a canvas just enough for rending descadants.  The
-* of adjusting is zeroing.
+* process of adjusting left-top of bounding box is zeroing.
 *
 * Following is rules.
 * - zeroing on a cached coord is performed by adjust coord_t::aggr_matrix
 *   of the cached coord and descendnats.
 * - Clean coords works just like before without change.
 *   - in preorder
 * - never perform zeroing on root_coord.
-* - zeroing on cached coords marked with \ref COF_MUST_ZEROING.
+* - do zeroing on cached coords marked with \ref COF_MUST_ZEROING.
 *   - when clean a descendant that moves out-side of it's canvas,
 *     respective cached coord is marked with \ref COF_MUST_ZEROING.
 *   - zeroing is performed immediately after clean coords.
-*   - zeroing will not propagate acrossing boundary of cached coord.
+*   - zeroing will not be propagated to ancestors of a cached coord.
-*     - It will be stopped at descendants which are cached coords.
+*     - It will be stopped once a cached coord being found.
 *     - coord_t::cur_area and coord_t::aggr_matrix of cached coords
 *       must be ajdusted.
 * - the area of a cached coord is defined in parent space.
 *   - areas of descendants are defined in space defined by aggr_matrix of
 *     cached coord.
-*   - parent know the area in where cached coord and descendnats will
+*     - coord_t::aggr_matrix of cached coord defines coordination of
+*       descendants.
+*   - the parent knows the area in where cached coord and descendnats will
 *     be draw.
 * - cached coords keep their private dirty area list.
 *   - private dirty areas of a cached coord are transformed and added to
 *     parent cached coord.
 *   - aggregates areas before adding to parent.
 area->h = h;
 DARRAY_CLEAN(_coord_get_dirty_areas(coord));
 add_dirty_area(rdman, coord, area);
 }
-/*! \brief Add canvas owner of dirty geos to coord_t::zeroing_coords.
+/*! \brief Add canvas owner of dirty geos to redraw_man_t::zeroing_coords.
 *
 * All possible coords that need a zeroing have at least one dirty geo.
 */
 static int add_rdman_zeroing_coords(redraw_man_t *rdman) {
 int i;
 int n_dirty_geos;
 geo_t **dirty_geos, *geo;
 int n_dirty_coords;
 coord_t **dirty_coords, *coord;
+/* Mark all cached ancestor coords of dirty geos */
 n_dirty_geos = rdman->dirty_geos.num;
 dirty_geos = rdman->dirty_geos.ds;
 for(i = 0; i < n_dirty_geos; i++) {
 	geo = dirty_geos[i];
 	coord = geo_get_coord(geo)->canvas_info->owner;
 		break;
 	    coord = coord->parent->canvas_info->owner;
 	}
 }
+/* Mark all cached ancestor coords of dirty coords */
 n_dirty_coords = rdman->dirty_coords.num;
 dirty_coords = rdman->dirty_coords.ds;
 for(i = 0; i < n_dirty_coords; i++) {
 	coord = dirty_coords[i]->canvas_info->owner;
 	while(!coord_get_flags(coord, COF_MUST_ZEROING | COF_TEMP_MARK)) {
 		break;
 	    coord = coord->parent->canvas_info->owner;
 	}
 }
+/* Add all marked coords into redraw_man_t::zeroing_coords list */
 FOR_COORDS_PREORDER(rdman->root_coord, coord) {
 	if(!coord_get_flags(coord, COF_TEMP_MARK)) {
 	    preorder_coord_skip_subtree(coord);
 	    continue;
 	}
 	add_zeroing_coord(rdman, coord);
 	coord_clear_flags(coord, COF_TEMP_MARK);
 }
 return OK;
 }
 	    DARRAY_CLEAN(_coord_get_dirty_areas(coord));
 	}
 	rdman->n_dirty_areas = 0;
 }
+/* clear COF_MUST_ZEROING flag for coords */
 coords = rdman->zeroing_coords.ds;
 for(i = 0; i < rdman->zeroing_coords.num; i++) {
 	coord = coords[i];
 	coord_clear_flags(coord, COF_MUST_ZEROING);
 }

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comparison src/redraw_man.c @ 519:7a1b17ebb3b4 Android_Skia