/**************************************************************************** * apps/graphics/traveler/tools/libwld/wld_addplane.c * This file contains the logic to add a plane to a world plane list * * Copyright (C) 2016 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * 3. Neither the name NuttX nor the names of its contributors may be * used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * ****************************************************************************/ /************************************************************************* * Included files *************************************************************************/ #include #include "wld_plane.h" /************************************************************************* * Public Functions *************************************************************************/ /************************************************************************* * Name: wld_add_plane * Description: * This function adds a plane to a world plane list ************************************************************************/ void wld_add_plane(rect_list_t * newRect, rect_head_t * list) { rect_list_t *next; rect_list_t *prev; /* Search the list to find the location to insert the new rectangle. Each * list is maintained in ascending plane order. */ for (next = list->head; ((next) && (next->d.plane < newRect->d.plane)); next = next->flink); /* Add the newRect to the spot found in the list. Check if the newRect goes * at the end of the list. */ if (!next) { /* No rectangle with plane larger than the one to be added was found in * the list. The newRect goes at the end of the list. */ prev = list->tail; if (!prev) { /* Special case: The list is empty */ newRect->flink = NULL; newRect->blink = NULL; list->head = newRect; list->tail = newRect; } else { newRect->flink = NULL; newRect->blink = prev; prev->flink = newRect; list->tail = newRect; } } else { /* The newRect goes just before next */ prev = next->blink; if (!prev) { /* Special case: Insert at the head of the list */ newRect->flink = next; newRect->blink = NULL; next->blink = newRect; list->head = newRect; } else { /* Insert in the middle of the list */ newRect->flink = next; newRect->blink = prev; prev->flink = newRect; next->blink = newRect; } } }