69 lines
1.6 KiB
C
69 lines
1.6 KiB
C
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/* dcel.c
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*
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* Created by Rory Healy (healyr@student.unimelb.edu.au)
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* Created on 25th August 2021
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* Last modified 25th August 2021
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*
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* Contains functions for the DCEL data structure, including creating,
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* splitting an edge, and identifying towers in faces.
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*
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*/
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#ifndef DCEL_HEADER
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#include "dcel.h"
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#endif
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#ifndef COMMON_HEADER
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#include "common.h"
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#endif
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struct halfEdge {
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halfEdge_t *previous;
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halfEdge_t *next;
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halfEdge_t *twin;
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int face;
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int edge;
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};
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struct vertex {
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double x;
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double y;
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};
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struct edge {
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halfEdge_t halfEdge;
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};
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struct face {
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halfEdge_t start;
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};
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/* Reads the polygon file and stores the information in the vertices array. */
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vertex_t **readPolygon(vertex_t **vertices, FILE *polygonFile, int *numVertices) {
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double currentX, currentY;
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int maxSizeVertices = 1;
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while ((fscanf(polygonFile, "%lf %lf", ¤tX, ¤tY)) != EOF) {
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/* Check if there enough space in the towers array */
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if (*numVertices == maxSizeVertices) {
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maxSizeVertices *= 2;
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vertex_t **temp = realloc(vertices, maxSizeVertices * sizeof(*vertices));
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checkNullPointer(temp);
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vertices = temp;
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}
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/* The current vertex being filled in with information */
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vertices[*numVertices] = malloc(sizeof(*vertices[*numVertices]));
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vertices[*numVertices]->x = currentX;
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vertices[*numVertices]->y = currentY;
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*numVertices += 1;
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}
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return vertices;
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}
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void freeVertices(vertex_t **vertices, int numVertices) {
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for (int i = 0; i < numVertices; i++) {
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free(vertices[i]);
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}
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free(vertices);
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}
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