Task 2 completed

.vscode/launch.json

@@ -0,0 +1,46 @@
+{
+    // Use IntelliSense to learn about possible attributes.
+    // Hover to view descriptions of existing attributes.
+    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+        {
+            "name": "Voronoi2 - 1",
+            "type": "cppdbg",
+            "request": "launch",
+            "program": "${workspaceFolder}/voronoi2",
+            "args": ["1", "pp_inside.txt", "output.txt"],
+            "stopAtEntry": false,
+            "cwd": "${fileDirname}",
+            "environment": [],
+            "externalConsole": false,
+            "MIMode": "gdb",
+            "setupCommands": [
+                {
+                    "description": "Enable pretty-printing for gdb",
+                    "text": "-enable-pretty-printing",
+                    "ignoreFailures": true
+                }
+            ]
+        },
+        {
+            "name": "Voronoi2 - 2",
+            "type": "cppdbg",
+            "request": "launch",
+            "program": "${workspaceFolder}/voronoi2",
+            "args": ["2", "pp_inside.txt", "polygon_square.txt", "output.txt"],
+            "stopAtEntry": false,
+            "cwd": "${fileDirname}",
+            "environment": [],
+            "externalConsole": false,
+            "MIMode": "gdb",
+            "setupCommands": [
+                {
+                    "description": "Enable pretty-printing for gdb",
+                    "text": "-enable-pretty-printing",
+                    "ignoreFailures": true
+                }
+            ]
+        }
+    ]
+}

Makefile

@@ -1,24 +1,8 @@
-# Link command:
-#voronoi1: common.o dcel.o voronoi.o main.o
-#	gcc -Wall -Wextra -Werror -pedantic -g -o voronoi1 main.o voronoi.o dcel.o common.o
-
-# Compilation commands:
-#common.o: common.c
-#	gcc -Wall -Wextra -Werror -pedantic -g -o common.o common.c -c
-#
-#dcel.o: dcel.c
-#	gcc -Wall -Wextra -Werror -pedantic -g -o dcel.o dcel.c -c
-#
-#voronoi.o: voronoi.c
-#	gcc -Wall -Wextra -Werror -pedantic -g -o voronoi.o voronoi.c -c
-#
-#main.o: main.c
-#	gcc -Wall -Wextra -Werror -pedantic -g -o main.o main.c -c
-
 # Link command:
 voronoi2: common.o towers.o dcel.o voronoi.o input.o main.o
-	gcc -Wall -Wextra -Werror -pedantic -g -o voronoi2 main.o input.o voronoi.o dcel.o towers.o common.o -lm
+	gcc -Wall -Wextra -Werror -pedantic -g -o voronoi2 main.o input.o voronoi.o dcel.o towers.o common.o
 
+# Compilation commands
 common.o: common.c
 	gcc -Wall -Wextra -Werror -pedantic -g -o common.o common.c -c
 
@@ -31,8 +15,8 @@ dcel.o: dcel.c
 voronoi.o: voronoi.c
 	gcc -Wall -Wextra -Werror -pedantic -g -o voronoi.o voronoi.c -c
 
-main.o: main.c
-	gcc -Wall -Wextra -Werror -pedantic -g -o main.o main.c -c
-
 input.o: input.c
 	gcc -Wall -Wextra -Werror -pedantic -g -o input.o input.c -c
+
+main.o: main.c
+	gcc -Wall -Wextra -Werror -pedantic -g -o main.o main.c -c

common.h

@@ -19,13 +19,6 @@
 
 #endif
 
-#ifndef MATH_HEADER
-#define MATH_HEADER
-
-#include <math.h>
-
-#endif
-
 #ifndef COMMON_HEADER
 #define COMMON_HEADER
 

dcel.c

@@ -2,7 +2,7 @@
  *
  * Created by Rory Healy (healyr@student.unimelb.edu.au)
  * Created on 25th August 2021
- * Last modified 11th September 2021
+ * Last modified 13th September 2021
  *
  * Contains functions for the DCEL data structure, including initialisation, 
  * splitting an edge, and identifying towers in faces.
@@ -16,74 +16,145 @@
 #include "dcel.h"
 #endif
 
-/* Deprecated by Grady's sample solution */
+void freePoints(vertex_t **points, int numPoints) {
-vertex_t **readPolygon(vertex_t **vertices, FILE *polygonFile, \
+    for (int i = 0; i < numPoints; i++) {
-    int *numVertices) {
+        free(points[i]);
-    double currentX, currentY;
+    }
-    int maxSizeVertices = 1;
+    free(points);
-    while ((fscanf(polygonFile, "%lf %lf", &currentX, &currentY)) != EOF) {
+}
-        /* Check if there enough space in the towers array */
+
-        if (*numVertices == maxSizeVertices) {
+void freeBisectors(bisector_t **bisectors, int numBisectors) {
-            maxSizeVertices *= 2;
+    for (int i = 0; i < numBisectors; i++) {
-            vertex_t **temp = realloc(vertices, \
+        free(bisectors[i]->mid);
-                maxSizeVertices * sizeof(*vertices));
+        free(bisectors[i]);
+    }
+    free(bisectors);
+}
+
+void freeIntersections(intersection_t **intersections, int numIntersections) {
+    for (int i = 0; i < numIntersections; i++) {
+        free(intersections[i]->fromPoint);
+        free(intersections[i]->toPoint);
+        free(intersections[i]);
+    }
+    free(intersections);
+}
+
+bisector_t **getBisectors(bisector_t **bisectors, vertex_t **points, \
+    int numBisectors) {
+    for (int i = 0; i < numBisectors; i++) {
+        bisectors[i] = malloc(sizeof(*bisectors[i]));
+        bisectors[i]->mid = malloc(sizeof(*bisectors[i]->mid));
+
+        /* Calculate midpoint of the two points */
+        bisectors[i]->mid->x = (points[2 * i]->x + points[2 * i + 1]->x) / 2;
+        bisectors[i]->mid->y = (points[2 * i]->y + points[2 * i + 1]->y) / 2;
+
+        /* Calculating bisector slope according to slope of AB */
+        if (points[2 * i]->x == points[2 * i + 1]->x) {
+            /* The line segment AB has an infinite gradient, 
+             * so the orthogonal line will have zero slope.
+             */
+            bisectors[i]->slope = 0;
+            bisectors[i]->isSlopeInfinite = 0;
+        } else if (points[2 * i]->y == points[2 * i + 1]->y) {
+            /* The line segment AB has gradient of zero, so 
+             * the orthogonal line will have an infinite slope. 
+             */
+            bisectors[i]->isSlopeInfinite = 1;
+
+            /* Not actually zero, just a placeholder to prevent 
+             * accidental errors 
+             */
+            bisectors[i]->slope = 0;
+        } else {
+            /* The line segment AB has a non-zero and finite gradient, 
+             * so the gradient of the bisector can be calculated.
+             */
+            bisectors[i]->isSlopeInfinite = 0;
+            bisectors[i]->slope = -1 / \
+                ((points[2 * i + 1]->y - points[2 * i]->y) / \
+                (points[2 * i + 1]->x - points[2 * i]->x));
+        }
+    }
+    
+    return bisectors;
+}
+
+vertex_t *getBisectorPoint(double distance, bisector_t *b, int direction) {
+    vertex_t *returnPoint = malloc(sizeof(*returnPoint));
+
+    if (b->isSlopeInfinite) {
+        /* Vertical line - just add vertical distance */
+        returnPoint->x = b->mid->x;
+        returnPoint->y = b->mid->y + (distance * direction);
+    } else if (b->slope == 0) {
+        /* Horizontal line - just add horizontal distance */
+        returnPoint->x = b->mid->x + (distance * direction);
+        returnPoint->y = b->mid->y;
+    } else {
+        /* Not horizontal or vertical - add distance to x, then find 
+         * y-intercept of the bisector, and plug it in to y = mx + c to find
+         * the corresponding y-value.
+         */
+        double c = b->mid->y - b->slope * b->mid->x;
+        returnPoint->x = b->mid->x + (distance * direction);
+        returnPoint->y = b->slope * returnPoint->x + c;
+    }
+
+    return returnPoint;
+}
+
+intersection_t *newIntersection() {
+    intersection_t *intersection = malloc(sizeof(*intersection));
+    checkNullPointer(intersection);
+
+    intersection->fromPoint = malloc(sizeof(*intersection->fromPoint));
+    checkNullPointer(intersection->fromPoint);
+
+    intersection->toPoint = malloc(sizeof(*intersection->toPoint));
+    checkNullPointer(intersection->toPoint);
+
+    return intersection;
+}
+
+vertex_t **readPoints(vertex_t **points, FILE *pointsFile, int *numPoints) {
+    /* Initial size of buffer is 1 as getline() reallocs as needed */
+    size_t lineBufferSize = 1;
+
+    /* Stores the current line from the points file */
+    char *lineBuffer = malloc(lineBufferSize * sizeof(*lineBuffer));
+    checkNullPointer(lineBuffer);
+
+    /* Assuming that pointsFile is valid, there must be at least two points */
+    int maxSizePoints = 2;
+
+    while (getline(&lineBuffer, &lineBufferSize, pointsFile) > 0) {
+        /* Ensure there is enough space in the points array */
+        if (*numPoints == maxSizePoints) {
+            maxSizePoints *= 2;
+            vertex_t **temp = realloc(points, maxSizePoints * sizeof(*points));
             checkNullPointer(temp);
-            vertices = temp;
+            points = temp;
         }
 
-        /* The current vertex being filled in with information */
+        double xCoordinateA, yCoordinateA, xCoordinateB, yCoordinateB;
-        vertices[*numVertices] = malloc(sizeof(*vertices[*numVertices]));
+        sscanf(lineBuffer, "%lf %lf %lf %lf", &xCoordinateA, &yCoordinateA, \
-        vertices[*numVertices]->x = currentX;
+            &xCoordinateB, &yCoordinateB);
-        vertices[*numVertices]->y = currentY;
-        *numVertices += 1;
-    }
-    return vertices;
-}
         
-void freeVertices(vertex_t **vertices, int numVertices) {
+        points[*numPoints] = malloc(sizeof(*points[*numPoints]));
-    for (int i = 0; i < numVertices; i++) {
+        points[*numPoints]->x = xCoordinateA;
-        free(vertices[i]);
+        points[*numPoints]->y = yCoordinateA;
-    }
+        *numPoints += 1;
-    free(vertices);
-}
 
-bisector_t *getBisector(vertex_t *pointA, vertex_t *pointB) {
+        points[*numPoints] = malloc(sizeof(*points[*numPoints]));
-    bisector_t *newBisector = malloc(sizeof(*newBisector));
+        points[*numPoints]->x = xCoordinateB;
-    checkNullPointer(newBisector);
+        points[*numPoints]->y = yCoordinateB;
-
+        *numPoints += 1;
-    double midpointX = (pointA->x + pointB->x) / 2;
-    double midpointY = (pointA->y + pointB->y) / 2;
-
-    newBisector->midX = midpointX;
-    newBisector->midY = midpointY;
-
-    /* Calculating bisector slope according to slope of AB */
-    if (pointA->x == pointB->x) {
-        /* The line segment AB has an infinite gradient, 
-         * so the orthogonal line will have zero slope.
-         */
-        newBisector->slope = 0;
-        newBisector->isSlopeInfinite = 0;
-    } else if (pointA->y == pointB->y) {
-        /* The line segment AB has gradient of zero, so 
-         * the orthogonal line will have an infinite slope. 
-         */
-        newBisector->isSlopeInfinite = 1;
-
-        /* Not actually zero, just a placeholder to prevent 
-         * accidental errors 
-         */
-        newBisector->slope = 0;
-    } else {
-        /* The line segment AB has a non-zero and finite gradient, 
-         * so the gradient of the bisector can be calculated.
-         */
-        newBisector->isSlopeInfinite = 0;
-        newBisector->slope = -1 / \
-            ((pointB->y - pointA->y) / (pointB->x - pointA->x));
     }
 
-    return newBisector;
+    free(lineBuffer);
+    return points;
 }
 
 /* Here on out is the base code from Grady, with some alterations from me */
@@ -99,48 +170,6 @@ bisector_t *getBisector(vertex_t *pointA, vertex_t *pointB) {
 #define OUTSIDE (-1)
 #define NODIAMETER (-1)
 
-double dist_2D(double x1, double y1, double x2, double y2) {
-    return sqrt(pow(x2 - x1, 2) + pow(y2 - y1, 2));
-}
-
-double inv_dist_2D(double x1, double y1, double m, double c1, double d) {
-    /* Solve sqrt((y - y1)^2 + (x - x1)^2) = d^2 for x by substituting 
-     * y = mx + c1, which gives an equation for x 
-     * Using this, you can find a point that lies on the line y = mx + c1
-     * that is of distance d away from (x1, y1).
-     */
-    double a = m * m + 1;
-    double b = 2 * c1 * m - 2 * x1 - 2 * m * y1;
-    double c = c1 * c1 + x1 * x1 + y1 * y1 - 2 * c1 * y1 - d * d;
-    return (-b + sqrt(b * b - 4 * a * c)) / (2 * a);
-}
-
-vertex_t *getBisectorPoint(double distance, bisector_t *b) {
-    vertex_t *returnPoint = malloc(sizeof(*returnPoint));
-    if (b->isSlopeInfinite) {
-        returnPoint->x = b->midX;
-        returnPoint->y = b->midY + distance;
-    } else if (b->slope == 0) {
-        returnPoint->x = b->midX + distance;
-        returnPoint->y = b->midY;
-    } else {
-        /* Find the y-intercept of the bisector, use it to find the general 
-         * form of the bisector in the form of y = mx + c
-         */
-        double c = b->midY - b->slope * b->midX;
-        returnPoint->x = inv_dist_2D(b->midX, b->midY, b->slope, c, distance);
-        returnPoint->y = b->slope * returnPoint->x + c;
-    }
-
-    /* Due to floating-point precision, there may be a situation where the 
-     * distance between the bisector midpoint and returnPoint is slightly less 
-     * than distance, but unless getBisectorPoint needs to guarentee that this 
-     * distance is greater than distance, it shouldn't be an issue.
-     */
-
-    return returnPoint;
-}
-
 /* 
 This intersection is based on code by Joseph O'Rourke and is provided for use in 
 COMP20003 Assignment 2.
@@ -246,14 +275,17 @@ enum intersectType intersects(halfEdge_t *he, bisector_t *b, \
     double heEy = dcel->vertices[he->endVertex].y;
     
     /* Bisector x, y twin */
-    double bSx = b->startX;
+    vertex_t *startPoint = getBisectorPoint(minLength, b, -1);
-    double bSy = b->startY;
+    vertex_t *endPoint = getBisectorPoint(minLength, b, 1);
-    double bEx = b->endX;
+    double bSx = startPoint->x;
-    double bEy = b->endY;
+    double bSy = startPoint->y;
+    double bEx = endPoint->x;
+    double bEy = endPoint->y;
+
+    free(startPoint);
+    free(endPoint);
     
     /* Fill in segment. */
-    // min-length not used here?
-    printf("In intersets(): minlength = %lf\n", minLength);
 
     /* Parametric equation parameters */
     double t1, t2;
@@ -344,53 +376,6 @@ enum intersectType intersects(halfEdge_t *he, bisector_t *b, \
     }
 }
 
-char *getIntersectionString(intersection_t *intersection) {
-    /*
-    
-    
-    
-    FILL IN
-
-
-
-    */
-    if (!intersection) {
-      return NULL;
-    }
-    char *returnString = NULL;
-    if (0 <= 0) {
-        /* Find out memory needed. */
-        int stringLength = snprintf(returnString, 0, 
-            "From Edge %d (%lf, %lf) to Edge %d (%lf, %lf)", 
-            0, 0.0, 0.0,
-            0, 0.0, 0.0);
-        returnString = malloc(sizeof(*returnString) * (stringLength + 1));
-        checkNullPointer(returnString);
-        sprintf(returnString, "From Edge %d (%lf, %lf) to Edge %d (%lf, %lf)", 
-            0, 0.0, 0.0,
-            0, 0.0, 0.0);
-    } else {
-        /* Find out memory needed. */
-        int stringLength = snprintf(returnString, 0, 
-            "From Edge %d (%lf, %lf) to Edge %d (%lf, %lf)", 
-            0, 0.0, 0.0,
-            0, 0.0, 0.0);
-        returnString = malloc(sizeof(*returnString) * (stringLength + 1));
-        checkNullPointer(returnString);
-        sprintf(returnString, "From Edge %d (%lf, %lf) to Edge %d (%lf, %lf)", 
-            0, 0.0, 0.0,
-            0, 0.0, 0.0);
-    }
-    return returnString;
-}
-
-void freeIntersection(intersection_t *intersection) {
-    if (!intersection) {
-        return;
-    }
-    free(intersection);
-}
-
 DCEL_t *newDCEL() {
     /* Setup DCEL. */
     DCEL_t *dcel = malloc(sizeof(*dcel));
@@ -1026,82 +1011,72 @@ int inFace(DCEL_t *dcel, double x, double y, int faceIndex) {
     return 1;
 }
 
-int getDCELPointCount(DCEL_t *dcel) {
+intersection_t **getIntersections(intersection_t **intersections, \
-    if (!dcel) {
+    int *numIntersections, bisector_t **bisectors, int numBisectors, \
-        return 0;
+    DCEL_t *dcel, int face, double minLength) {
+    int maxSizeIntersections = 1;
+
+    for (int i = 0; i < numBisectors; i++) {
+        intersection_t *currentIntersection = NULL;
+
+        /* Intersection coordinates */
+        double x, y;
+
+        /* Flag is raised when first intersection is found */
+        int isIntersectionFound = 0;
+        
+        halfEdge_t *startHE = (dcel->faces)[face].start;   
+        halfEdge_t *currentHE = startHE;
+        int startVertex = startHE->startVertex;
+        int first = 1;
+
+        /* Loop through the face until the starting vertex is reached */
+        while (first || currentHE->startVertex != startVertex) {
+            enum intersectType typeOfIntersection = \
+                intersects(currentHE, bisectors[i], dcel, minLength, &x, &y);
+            
+            switch (typeOfIntersection) {
+                case INTERSECT:
+                case SAME_LINE_OVERLAP:
+                case ENDS_OVERLAP:
+                    if (!isIntersectionFound) {
+                        /* First point of intersection */
+                        isIntersectionFound = 1;
+                        currentIntersection = newIntersection();
+                        currentIntersection->fromPoint->x = x;
+                        currentIntersection->fromPoint->y = y;
+                        currentIntersection->fromEdge = currentHE->edge;
+                    } else {
+                        /* Second point of intersection */
+                        currentIntersection->toPoint->x = x;
+                        currentIntersection->toPoint->y = y;
+                        currentIntersection->toEdge = currentHE->edge;
+                    }
+                    break;
+                case DOESNT_INTERSECT:
+                default:
+                    break;
+            }
+            currentHE = currentHE->next;
+            first = 0;
+        }
+
+        /* If there is an intersection, add it to the array */
+        if (currentIntersection != NULL) {
+            /* Ensure there is enough space in the array */
+            if (*numIntersections == maxSizeIntersections) {
+                maxSizeIntersections *= 2;
+                intersection_t **temp = realloc(intersections, maxSizeIntersections * sizeof(*intersections));
+                checkNullPointer(temp);
+                intersections = temp;
+            }
+
+            intersections[*numIntersections] = currentIntersection;
+            *numIntersections += 1;
+        }
     }
-    return dcel->verticesUsed;
-}
 
-double getDCELVertexX(DCEL_t *dcel, int vertex) {
+    return intersections;
-    return (dcel->vertices)[vertex].x;
-}
-
-double getDCELVertexY(DCEL_t *dcel, int vertex) {
-    return (dcel->vertices)[vertex].y;
-}
-
-int getDCELEdgeCount(DCEL_t *dcel) {
-    if (!dcel) {
-        return 0;
-    }
-    return dcel->edgesUsed;
-}
-
-int getDCELEdgeVertexStart(DCEL_t *dcel, int edge) {
-    if (!dcel) {
-        return 0;
-    }
-    return (dcel->edges)[edge].halfEdge->startVertex;
-}
-
-int getDCELEdgeVertexEnd(DCEL_t *dcel, int edge) {
-    if (!dcel) {
-        return 0;
-    }
-    return (dcel->edges)[edge].halfEdge->endVertex;
-}
-
-int getDCELEdgeVertexPairStart(DCEL_t *dcel, int edge) {
-    if (!dcel) {
-        return 0;
-    }
-    return (dcel->edges)[edge].halfEdge->twin->startVertex;
-}
-
-int getDCELEdgeVertexPairEnd(DCEL_t *dcel, int edge) {
-    if (!dcel) {
-        return 0;
-    }
-    return (dcel->edges)[edge].halfEdge->twin->endVertex;
-}
-
-int DCELhasEdge(DCEL_t *dcel, int edge) {
-    if ((dcel->edges)[edge].halfEdge->face != NOFACE) {
-        return 1;
-    } else {
-        return 0;
-    }
-}
-
-int DCELhasEdgePair(DCEL_t *dcel, int edge) {
-    if ((dcel->edges)[edge].halfEdge->face == NOFACE) {
-        return 0;
-    }
-    if ((dcel->edges)[edge].halfEdge->twin) {
-        return 1;
-    } else {
-        return 0;
-    }
-}
-
-intersection_t *getIntersection(bisector_t *b, DCEL_t *dcel, int face,
-    double minLength) {
-    // FILL IN
-    printf("In getIntersection(): bisector start: %lf, dcel numfaces = %d" \
-        "face = %d, minLength = %lf\n", b->startX, dcel->facesAllocated, \
-        face, minLength);
-    return NULL;
 }
 
 double getDiameter(DCEL_t *dcel, int faceIndex) {

dcel.h

@@ -20,25 +20,15 @@ typedef struct vertex {
 } vertex_t;
 
 typedef struct bisector {
-    double startX;
+    vertex_t *mid;
-    double startY;
-    double endX;
-    double endY;
-
-    /* This refers to the midpoint of the line segment AB, not the midpoint
-     * of the bisector itself.
-     */
-    double midX;
-    double midY;
-
     int isSlopeInfinite;
     double slope;
 } bisector_t;
 
-typedef struct halfEdgeLabel {
+typedef struct halfEdge {
-    struct halfEdgeLabel *previous;
+    struct halfEdge *previous;
-    struct halfEdgeLabel *next;
+    struct halfEdge *next;
-    struct halfEdgeLabel *twin;
+    struct halfEdge *twin;
     int face;
     int edge;
     int startVertex;
@@ -47,6 +37,7 @@ typedef struct halfEdgeLabel {
 
 typedef struct edge {
     halfEdge_t *halfEdge;
+    tower_t *tower;
 } edge_t;
 
 typedef struct face {
@@ -63,7 +54,10 @@ typedef struct split {
 } split_t;
 
 typedef struct intersection {
-    vertex_t intersectionPoint;
+    int fromEdge;
+    int toEdge;
+    vertex_t *fromPoint;
+    vertex_t *toPoint;
 } intersection_t;
 
 typedef struct DCEL {
@@ -136,9 +130,6 @@ int vertexMatch(vertex_t *v1, vertex_t *v2);
 /* Gets the string for the given bisector equation. */
 char *getBisectorEquation(bisector_t *b);
 
-/* Frees the given bisector. */
-void freeBisector(bisector_t *bisector);
-
 /* Representation of no face */
 #define NOFACE (-1)
 
@@ -148,18 +139,6 @@ void freeBisector(bisector_t *bisector);
 /* Default minimum length for bisector in each direction */
 #define DEFAULTMINLENGTH (200)
 
-/* Gets the intersection between the given bisector and the given DCEL
- * for the given face. 
- */
-intersection_t *getIntersection(bisector_t *b, DCEL_t *dcel, \
-    int face, double minLength);
-
-/* Gets the string for the given intersection. */
-char *getIntersectionString(intersection_t *intersection);
-
-/* Frees a given intersection. */
-void freeIntersection(intersection_t *intersection);
-
 /* Applies a given split to the DCEL. */
 void applySplit(split_t *split, DCEL_t *dcel);
 
@@ -172,6 +151,13 @@ int getFaceCount(DCEL_t *dcel);
 /* Returns 1 if the given x,y point is inside the given face. */
 int inFace(DCEL_t *dcel, double x, double y, int faceIndex);
 
+/* Gets the intersection between the given bisector and the given DCEL
+ * for the given face. 
+ */
+intersection_t **getIntersections(intersection_t **intersections, \
+    int *numIntersections, bisector_t **bisectors, int numBisectors, \
+    DCEL_t *dcel, int face, double minLength);
+
 /* Gets the diameter of the given face. */
 double getDiameter(DCEL_t *dcel, int faceIndex);
 
@@ -180,60 +166,7 @@ double getDiameter(DCEL_t *dcel, int faceIndex);
  */
 void incrementalVoronoi(DCEL_t *dcel, tower_t *watchTower);
 
-/* Returns the number of vertices in the DCEL. */
+/* O'Rourke's intersection functions */
-int getDCELPointCount(DCEL_t *dcel);
-
-/* Get x value of given vertex in DCEL. */
-double getDCELVertexX(DCEL_t *dcel, int vertex);
-
-/* Get y value of given vertex in DCEL. */
-double getDCELVertexY(DCEL_t *dcel, int vertex);
-
-/* Returns the number of edges in the DCEL. */
-int getDCELEdgeCount(DCEL_t *dcel);
-
-/* Get start vertex of given edge in DCEL. */
-int getDCELEdgeVertexStart(DCEL_t *dcel, int edge);
-
-/* Get end vertex of given edge in DCEL. */
-int getDCELEdgeVertexEnd(DCEL_t *dcel, int edge);
-
-/* Get start vertex of paired given edge in DCEL. */
-int getDCELEdgeVertexPairStart(DCEL_t *dcel, int edge);
-
-/* Get end vertex of paired given edge in DCEL. */
-int getDCELEdgeVertexPairEnd(DCEL_t *dcel, int edge);
-
-/* Check if the DCEL has the given edge. */
-int DCELhasEdge(DCEL_t *dcel, int edge);
-
-/* Check if the DCEL has a pair for the given edge. */
-int DCELhasEdgePair(DCEL_t *dcel, int edge);
-
-/* My own functions */
-
-/* Reads the polygon file and stores the information in the vertices array */
-vertex_t **readPolygon(vertex_t **vertices, FILE *polygonFile, \
-    int *numVertices);
-
-/* Frees an array of vertices */
-void freeVertices(vertex_t **vertices, int numVertices);
-
-/* Calculates and returns the equation of a bisector of two points */
-bisector_t *getBisector(vertex_t *pointA, vertex_t *pointB);
-
-/* Euclidian distance between two 2D points */
-double dist_2D(double x1, double y1, double x2, double y2);
-
-/* Returns a value for x that ensures the point (x, y) is at least d (distance) 
- * away from (x1, y1) whilst ensuring (x, y) is on the line y = mx + c1.
- */
-double inv_dist_2D(double x1, double y1, double m, double c, double d);
-
-/* Returns a point at least distance away from the midpoint of the bisector given */
-vertex_t *getBisectorPoint(double distance, bisector_t *b);
-
-/* O'Rourke's functions */
 /* Returns -1, 0 or 1, based on the area enclosed by the three points. 0 corresponds
     to no area enclosed.
 */
@@ -254,8 +187,42 @@ enum intersectType parallelIntersects(double heSx, double heSy, \
     double heEx, double heEy, double bSx, double bSy, \
     double bEx, double bEy, double *x, double *y);
 
-/* Tests if  */
+/* Tests if a half edge and a bisector intersect */
 enum intersectType intersects(halfEdge_t *he, bisector_t *b, \
     DCEL_t *dcel, double minLength, double *x, double *y);
 
+/* My own functions */
+
+/* Reads the polygon file and stores the information in the vertices array */
+vertex_t **readPolygon(vertex_t **vertices, FILE *polygonFile, \
+    int *numVertices);
+
+/* Frees an array of vertices */
+void freeVertices(vertex_t **vertices, int numVertices);
+
+/* Calculates and returns the equation of a bisector of two points */
+bisector_t **getBisectors(bisector_t **bisectors, vertex_t **points, \
+    int numPoints);
+
+/* Returns a point at least distance away from the midpoint of the 
+ * bisector given. If direction is 0, then the point is +distance away in the 
+ * x-direction, otherwise -distance away in the x-direction.
+ */
+vertex_t *getBisectorPoint(double distance, bisector_t *b, int direction);
+
+/* Create a new intersection */
+intersection_t *newIntersection();
+
+/* Frees an array of bisectors */
+void freeBisectors(bisector_t **bisectors, int numBisectors);
+
+/* Frees an array of points */
+void freePoints(vertex_t **points, int numPoints);
+
+/* Frees an array of intersections */
+void freeIntersections(intersection_t **intersections, int numIntersections);
+
+/* Reads a points file and stores the information in the points array */
+vertex_t **readPoints(vertex_t **points, FILE *pointsFile, int *numPoints);
+
 #endif

input.c

@@ -5,7 +5,7 @@
  * Last modified 9th September 2021
  *
  * Contains functions for ensuring correct input arguments are given for 
- * each stage of the voronoi2 program.
+ * each stage of the voronoi2 program. Adapted from Grady's base code on Ed.
  * 
  */
 

main.c

@@ -12,14 +12,6 @@
  *
  */
 
-#ifndef DCEL_HEADER
-#include "dcel.h"
-#endif
-
-#ifndef COMMON_HEADER
-#include "common.h"
-#endif
-
 #ifndef VORONOI_HEADER
 #include "voronoi.h"
 #endif
@@ -28,38 +20,6 @@
 #include "input.h"
 #endif
 
-// int main(int argc, char **argv) {
-//     /* Input and output files */
-//     FILE *datasetFile = NULL, *polygonFile = NULL, *outputFile = NULL;
-//     checkInputArgs(argc, argv, &datasetFile, &polygonFile, &outputFile);
-
-//     /* Stores information about the towers given in dataset file */
-//     tower_t **towers = malloc(sizeof(*towers));
-//     checkNullPointer(towers);
-//     int numTowers = 0;
-//     towers = readTowers(towers, datasetFile, &numTowers);
-
-//     /* Stores information about the vertices in the polygon file */
-//     vertex_t **vertices = malloc(sizeof(*vertices));
-//     checkNullPointer(vertices);
-//     int numVertices = 0;
-//     vertices = readPolygon(vertices, polygonFile, &numVertices);
-
-//     /* Create DCEL structure from vertices */
-
-//     /* Check for splits, split the polygon if needed */
-    
-//     /* Counts towers in each polygon, outputs to outputFile */
-
-//     /* Cleaning up data */
-//     freeTowers(towers, numTowers);
-//     freeVertices(vertices, numVertices);
-//     fclose(datasetFile);
-//     fclose(polygonFile);
-//     fclose(outputFile);
-//     return 0;
-// }
-
 int main(int argc, char **argv) {
     /* Ensure input arguments are correct */
     if (argc == 1) {
@@ -96,7 +56,7 @@ int main(int argc, char **argv) {
         /* Return error if stage number isn't defined. */  
         case STAGE_ERROR:
         default:
-            fprintf(stderr, "Stage was not handled ENUM value (%d)\n", stage);
+            printArgError(stage, "Invalid stage entered.");
             exit(EXIT_FAILURE);
     }
 

output.txt

@@ -0,0 +1,6 @@
+From Edge 0 (140.900000, -34.700000) to Edge 2 (150.000000, -34.700000)
+From Edge 0 (140.900000, -35.200000) to Edge 2 (150.000000, -35.200000)
+From Edge 1 (147.100000, -33.900000) to Edge 3 (147.100000, -39.200000)
+From Edge 1 (147.100000, -33.900000) to Edge 3 (147.100000, -39.200000)
+From Edge 1 (147.600000, -33.900000) to Edge 3 (147.600000, -39.200000)
+From Edge 1 (146.900000, -33.900000) to Edge 3 (141.600000, -39.200000)

towers.c

@@ -1,4 +1,13 @@
-
+/* voronoi.c
+ *
+ * Created by Rory Healy (healyr@student.unimelb.edu.au)
+ * Created on 11th September 2021
+ * Last modified 13th September 2021
+ *
+ * Contains functions for reading a CSV of watchtower information into an 
+ * array of towers.
+ * 
+ */
 
 #ifndef TOWERS_HEADER
 #include "towers.h"
@@ -10,7 +19,7 @@
 #define NUM_CSV_FIELDS 6
 
 tower_t **readTowers(tower_t **towers, FILE *datasetFile, int *numTowers) {
-    /* Maximum length of a single CSV line */
+    /* Maximum length of a single CSV line (+1 for null char in string) */
     size_t lineBufferSize = MAX_CSV_ENTRY_LEN + 1;
 
     /* Stores the current line from the CSV */
@@ -22,7 +31,7 @@ tower_t **readTowers(tower_t **towers, FILE *datasetFile, int *numTowers) {
     /* Discard the header line, then read the rest of the CSV */
     getline(&lineBuffer, &lineBufferSize, datasetFile);
     while (getline(&lineBuffer, &lineBufferSize, datasetFile) > 0) {
-        /* Check if there enough space in the towers array */
+        /* Ensure there is enough space in the towers array */
         if (*numTowers == maxSizetowers) {
             maxSizetowers *= 2;
             tower_t **temp = realloc(towers, maxSizetowers * sizeof(*towers));

voronoi.c

@@ -2,75 +2,32 @@
  *
  * Created by Rory Healy (healyr@student.unimelb.edu.au)
  * Created on 12th August 2021
- * Last modified 11th September 2021
+ * Last modified 13th September 2021
  *
  * Contains functions involving the generation of the Voronoi diagram, and 
  * running each stage of the assignment.
  * 
  */
 
-#ifndef COMMON_HEADER
-#include "common.h"
-#endif
-
 #ifndef VORONOI_HEADER
 #include "voronoi.h"
 #endif
 
-vertex_t **readPoints(vertex_t **points, FILE *pointsFile, int *numPoints) {
-    /* Initial size of buffer is 1 as getline() reallocs as needed */
-    size_t lineBufferSize = 1;
-
-    /* Stores the current line from the points file */
-    char *lineBuffer = malloc(lineBufferSize * sizeof(*lineBuffer));
-    checkNullPointer(lineBuffer);
-
-    /* Assuming that pointsFile is valid, there must be at least two points */
-    int maxSizePoints = 2;
-
-    while (getline(&lineBuffer, &lineBufferSize, pointsFile) > 0) {
-        /* Check if there is enough space in the points array */
-        if (*numPoints == maxSizePoints) {
-            maxSizePoints *= 2;
-            vertex_t **temp = realloc(points, maxSizePoints * sizeof(*points));
-            checkNullPointer(temp);
-            points = temp;
-        }
-
-        double xCoordinateA, yCoordinateA, xCoordinateB, yCoordinateB;
-        sscanf(lineBuffer, "%lf %lf %lf %lf", &xCoordinateA, &yCoordinateA, \
-            &xCoordinateB, &yCoordinateB);
-        
-        points[*numPoints] = malloc(sizeof(*points[*numPoints]));
-        points[*numPoints]->x = xCoordinateA;
-        points[*numPoints]->y = yCoordinateA;
-        *numPoints += 1;
-
-        points[*numPoints] = malloc(sizeof(*points[*numPoints]));
-        points[*numPoints]->x = xCoordinateB;
-        points[*numPoints]->y = yCoordinateB;
-        *numPoints += 1;
-    }
-
-    free(lineBuffer);
-    return points;
-}
-
 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->midX);
+        fprintf(outputFile, "x = %lf\n", bisector->mid->x);
     } else {
         fprintf(outputFile, "y = %lf * (x - %lf) + %lf\n", \
-            bisector->slope, bisector->midX,  bisector->midY);
+            bisector->slope, bisector->mid->x,  bisector->mid->y);
     }
 }
 
-void freePoints(vertex_t **points, int numPoints) {
+void stage2PrintIntersection(intersection_t *intersection, FILE *outputFile) {
-    for (int i = 0; i < numPoints; i++) {
+    fprintf(outputFile, "From Edge %d (%lf, %lf) to Edge %d (%lf, %lf)\n", \
-        free(points[i]);
+        intersection->fromEdge, intersection->fromPoint->x, \
-    }
+        intersection->fromPoint->y, intersection->toEdge, \
-    free(points);
+        intersection->toPoint->x, intersection->toPoint->y);
 }
 
 void stage1(char *pointsFileName, char *outputFileName) {
@@ -84,23 +41,27 @@ void stage1(char *pointsFileName, char *outputFileName) {
     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 < numPoints; i += 2) {
+    for (int i = 0; i < numBisectors; i++) {
-        bisector_t *currBisector = getBisector(points[i], points[i + 1]);
+        stage1PrintBisector(bisectors[i], outputFile);
-        stage1PrintBisector(currBisector, outputFile);
-        free(currBisector);
     }
 
     /* Clean up */
     freePoints(points, numPoints);
+    freeBisectors(bisectors, numBisectors);
     fclose(pointsFile);
     fclose(outputFile);
 }
 
 void stage2(char *pointsFileName, char *polygonFileName, char *outputFileName) {
-    FILE *pointsFile = NULL, *polygonFile = NULL, *outputFile = NULL;
+    FILE *pointsFile = NULL, *outputFile = NULL;
     pointsFile = safeFileOpen(&pointsFile, pointsFileName, "r");
-    polygonFile = safeFileOpen(&polygonFile, polygonFileName, "r");
     outputFile = safeFileOpen(&outputFile, outputFileName, "w");
 
     /* Points are given as pairs, so initialise 2 points */
@@ -109,17 +70,32 @@ void stage2(char *pointsFileName, char *polygonFileName, char *outputFileName) {
     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(polygonFile);
     fclose(outputFile);
 }
 

voronoi.h

@@ -5,14 +5,11 @@
 #ifndef VORONOI_HEADER
 #define VORONOI_HEADER
 
-/* Reads a points file and stores the information in the points array */
-vertex_t **readPoints(vertex_t **points, FILE *pointsFile, int *numPoints);
-
 /* Prints bisectors to an output file */
 void stage1PrintBisector(bisector_t *bisector, FILE *outputFile);
 
-/* Frees all points from a points array */
+/* Prints intersections to an output file */
-void freePoints(vertex_t **points, int numPoints);
+void stage2PrintIntersection(intersection_t *intersection, FILE *outputFile);
 
 /* Outputs the bisector equations from pointsFile into outputFile */
 void stage1(char *pointsFileName, char *outputFileName);