comp20003-project02/voronoi.c

/* voronoi.c
 *
 * Created by Rory Healy (healyr@student.unimelb.edu.au)
 * Created on 12th August 2021
 * Last modified 14th September 2021
 *
 * Contains functions involving the generation of the Voronoi diagram, and 
 * running each stage of the assignment.
 * 
 */

#ifndef VORONOI_HEADER
#include "voronoi.h"
#endif

void stage1PrintBisector(bisector_t *bisector, FILE *outputFile) {
    if (bisector->isSlopeInfinite) {
        /* Cannot print infinite slope, so print only x-intercept */
        fprintf(outputFile, "x = %lf\n", bisector->mid->x);
    } else {
        fprintf(outputFile, "y = %lf * (x - %lf) + %lf\n", \
            bisector->slope, bisector->mid->x,  bisector->mid->y);
    }
}

void stage2PrintIntersection(intersection_t *intersection, FILE *outputFile) {
    fprintf(outputFile, "From Edge %d (%lf, %lf) to Edge %d (%lf, %lf)\n", \
        intersection->fromEdge, intersection->fromPoint->x, \
        intersection->fromPoint->y, intersection->toEdge, \
        intersection->toPoint->x, intersection->toPoint->y);
}

void stage34PrintTowers(tower_t *tower, FILE *outputFile, double diameter) {
    fprintf(outputFile, "Watchtower ID: %s, Postcode: %s, Population " \
        "Served: %d, Watchtower Point of Contact Name: %s, x: %lf, y: %lf, " \
        "Diameter of Cell: %lf\n", tower->id, tower->postcode, \
        tower->population, tower->manager, tower->x, tower->y, diameter);
}

int getFaceTowerIsIn(DCEL_t *dcel, tower_t *tower) {
    for (int i = 0; i < getFaceCount(dcel); i++) {
        if (inFace(dcel, tower->x, tower->y, i)) {
            return i;
        }
    }
    return -1;
}

void incrementalVoronoi(DCEL_t *voronoi, tower_t *tower) {
    int faceTowerIsIn = getFaceTowerIsIn(voronoi, tower);
    if (faceTowerIsIn == -1) {
        fprintf(stderr, "Error: Watchtower %s is outside the polygon.\n", \
            tower->id);
        exit(EXIT_FAILURE);
    }
}

DCEL_t *newVoronoi(DCEL_t *voronoi, tower_t *towerA, tower_t *towerB) {    
    /* Get vertices from towers */
    vertex_t *pointA = getAPoint(towerA->x, towerA->y);
    vertex_t *pointB = getAPoint(towerB->x, towerB->y);

    /* Create first bisector */
    bisector_t *bisector = newBisector();
    bisector = getABisector(bisector, pointA, pointB);

    /* Get intersection of bisector with the polygon */
    intersection_t *intersection = NULL;
    intersection = getAnIntersection(intersection, voronoi, bisector, \
        DEFAULT_FACE, DEFAULTMINLENGTH);
    
    if (intersection) {
        free(intersection->fromPoint);
        free(intersection->toPoint);
        free(intersection);
    }

    free(bisector->mid);
    free(bisector);
    free(pointA);
    free(pointB);
    return voronoi;
}

void stage1(char *pointsFileName, char *outputFileName) {
    FILE *pointsFile = NULL, *outputFile = NULL;
    pointsFile = safeFileOpen(&pointsFile, pointsFileName, "r");
    outputFile = safeFileOpen(&outputFile, outputFileName, "w");
    
    /* Points are given as pairs, so initialise 2 points */
    vertex_t **points = malloc(sizeof(*points) * 2);
    checkNullPointer(points);
    int numPoints = 0;
    points = readPoints(points, pointsFile, &numPoints);

    /* There are half as many bisectors as points */
    int numBisectors = numPoints / 2;
    bisector_t **bisectors = malloc(sizeof(*bisectors) * numBisectors);
    checkNullPointer(bisectors);
    bisectors = getBisectors(bisectors, points, numBisectors);

    /* For each pair, calculate and print the bisector to outputFile */
    for (int i = 0; i < numBisectors; i++) {
        stage1PrintBisector(bisectors[i], outputFile);
    }

    /* Clean up */
    freePoints(points, numPoints);
    freeBisectors(bisectors, numBisectors);
    fclose(pointsFile);
    fclose(outputFile);
}

void stage2(char *pointsFileName, char *polygonFileName, \
    char *outputFileName) {
    
    FILE *pointsFile = NULL, *outputFile = NULL;
    pointsFile = safeFileOpen(&pointsFile, pointsFileName, "r");
    outputFile = safeFileOpen(&outputFile, outputFileName, "w");

    /* Points are given as pairs, so initialise 2 points */
    vertex_t **points = malloc(sizeof(*points) * 2);
    checkNullPointer(points);
    int numPoints = 0;
    points = readPoints(points, pointsFile, &numPoints);

    /* There are half as many bisectors as points */
    int numBisectors = numPoints / 2;
    bisector_t **bisectors = malloc(sizeof(*bisectors) * numBisectors);
    checkNullPointer(bisectors);
    bisectors = getBisectors(bisectors, points, numBisectors);

    /* Construct the DCEL from the polygon file */
    DCEL_t *dcel = readPolygonFile(polygonFileName);

    /* Calculate and print intersections to the output file */
    intersection_t **intersections = malloc(sizeof(*intersections));
    checkNullPointer(intersections);
    int numIntersections = 0;
    intersections = getIntersections(intersections, &numIntersections, \
        bisectors, numBisectors, dcel, DEFAULT_FACE, DEFAULTMINLENGTH);

    for (int i = 0; i < numIntersections; i++) {
        stage2PrintIntersection(intersections[i], outputFile);
    }

    /* Clean up */
    freePoints(points, numPoints);
    freeBisectors(bisectors, numBisectors);
    freeIntersections(intersections, numIntersections);
    freeDCEL(dcel);
    fclose(pointsFile);
    fclose(outputFile);
}

void stage3(char *dataFileName, char *polygonFileName, char *outputFileName) {
    FILE *dataFile = NULL, *polygonFile = NULL, *outputFile = NULL;
    dataFile = safeFileOpen(&dataFile, dataFileName, "r");
    polygonFile = safeFileOpen(&polygonFile, polygonFileName, "r");
    outputFile = safeFileOpen(&outputFile, outputFileName, "w");

    /* Read towers from the data file */
    tower_t **towers = malloc(sizeof(*towers));
    checkNullPointer(towers);
    int numTowers = 0;
    towers = readTowers(towers, dataFile, &numTowers);

    /* Construct the DCEL from the polygon file */
    DCEL_t *dcel = readPolygonFile(polygonFileName);

    /* Add each tower to the Voronoi DCEL */

    /* Get diameters and output to outputFile */
    
    /* Clean up */
    freeDCEL(dcel);
    freeTowers(towers, numTowers);
    fclose(dataFile);
    fclose(polygonFile);
    fclose(outputFile);
}

void stage4(char *dataFileName, char *polygonFileName, char *outputFileName) {
    FILE *dataFile = NULL, *polygonFile = NULL, *outputFile = NULL;
    dataFile = safeFileOpen(&dataFile, dataFileName, "r");
    polygonFile = safeFileOpen(&polygonFile, polygonFileName, "r");
    outputFile = safeFileOpen(&outputFile, outputFileName, "w");

    /* Read towers from the data file */
    tower_t **towers = malloc(sizeof(*towers));
    checkNullPointer(towers);
    int numTowers = 0;
    towers = readTowers(towers, dataFile, &numTowers);

    /* Construct the DCEL from the polygon file */
    DCEL_t *dcel = readPolygonFile(polygonFileName);

    /* Add each tower to the Voronoi DCEL */

    /* Get diameters and sort, then output to outputFile */

    /* Clean up */
    freeDCEL(dcel);
    freeTowers(towers, numTowers);
    fclose(dataFile);
    fclose(polygonFile);
    fclose(outputFile);
}