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-rw-r--r--geometry.c368
1 files changed, 0 insertions, 368 deletions
diff --git a/geometry.c b/geometry.c
deleted file mode 100644
index d54348f..0000000
--- a/geometry.c
+++ /dev/null
@@ -1,368 +0,0 @@
-#include "geometry.h"
-#include <math.h>
-#include <stdlib.h>
-#include <gtk/gtk.h>
-
-
-void addVertex(VERTEX_LIST *list, const VERTEX *v) {
- list->nVertices++;
- list->vertices = realloc(list->vertices, list->nVertices*sizeof(VERTEX));
- list->vertices[list->nVertices-1] = *v;
-}
-
-void insertVertex(VERTEX_LIST *list, const VERTEX *v, unsigned int n) {
- int i;
-
- if(n > list->nVertices)
- n = list->nVertices;
-
- list->nVertices++;
- list->vertices = realloc(list->vertices, list->nVertices*sizeof(VERTEX));
-
- for(i = list->nVertices-1; i > n; i--)
- list->vertices[i] = list->vertices[i-1];
-
- list->vertices[n] = *v;
-}
-
-void deleteVertex(VERTEX_LIST *list, unsigned int n) {
- int i;
-
- list->nVertices--;
-
- for(i = n; i < list->nVertices; i++)
- list->vertices[i] = list->vertices[i+1];
-
- list->vertices = realloc(list->vertices, list->nVertices*sizeof(VERTEX));
-}
-
-double vertexDistanceSquare(const VERTEX *v1, const VERTEX *v2) {
- return (v1->x-v2->x)*(v1->x-v2->x) + (v1->y-v2->y)*(v1->y-v2->y);
-}
-
-double vertexDistance(const VERTEX *v1, const VERTEX *v2) {
- return sqrt(vertexDistanceSquare(v1, v2));
-}
-
-int vertexOnLine(const VERTEX *v, const LINE *l) {
- if(l->v1.x == l->v2.x && l->v1.y == l->v2.y) {
- if(l->v1.x == v->x && l->v1.y == v->y) return 1;
- else return 0;
- }
-
- if(l->v1.x == l->v2.x) {
- if(l->v1.x != v->x) return 0;
- else if(v->y >= MIN(l->v1.y, l->v2.y) && v->y <= MAX(l->v1.y, l->v2.y)) return 1;
- else return 1;
- }
-
- if(l->v1.y == l->v2.y) {
- if(l->v1.y != v->y) return 0;
- else if(v->x >= MIN(l->v1.x, l->v2.x) && v->x <= MAX(l->v1.x, l->v2.x)) return 1;
- else return 1;
- }
- if((v->x-l->v1.x)/(l->v2.x-l->v1.x) - (v->y-l->v1.y)/(l->v2.y-l->v1.y) == 0) return 1;
- else return 0;
-}
-
-int vertexInRect(const VERTEX *v, const RECTANGLE *rect) {
- int ret = EDGE_NONE;
-
- if(v->x < rect->x) ret |= EDGE_LEFT;
- else if(v->x >= rect->x+rect->width) ret |= EDGE_RIGHT;
-
- if(v->y < rect->y) ret |= EDGE_TOP;
- else if(v->y >= rect->y+rect->height) ret |= EDGE_BOTTOM;
-
- return ret;
-}
-
-static int quadrant(VERTEX *v) {
- if(v->x > 0 && v->y >= 0) return 1;
- if(v->x >= 0 && v->y < 0) return 2;
- if(v->x < 0 && v->y <= 0) return 3;
- if(v->x <= 0 && v->y > 0) return 4;
-
- return 0;
-}
-
-gboolean vertexInPolygon(const VERTEX *v, const POLYGON *p) {
- int d = 0, i, li;
- int q, ql, q2;
- LINE d1 = {{-1, -1}, {1, 1}};
- LINE d2 = {{-1, 1}, {1, -1}};
- LINE l;
- VERTEX v2;
-
-
- if(p->nVertices == 0) return FALSE;
-
- v2.x = p->vertices[p->nVertices-1].x - v->x;
- v2.y = p->vertices[p->nVertices-1].y - v->y;
- q = quadrant(&v2);
-
- if(q == 0) return TRUE;
-
- for(i = 0; i < p->nVertices; i++) {
- ql = q;
-
- v2.x = p->vertices[i].x - v->x;
- v2.y = p->vertices[i].y - v->y;
- q = quadrant(&v2);
-
- if(q == 0) return TRUE;
-
- switch(q-ql) {
- case 0:
- break;
- case 1:
- case -3:
- d++;
- break;
- case 3:
- case -1:
- d--;
- break;
- default:
- l.v1.x = p->vertices[(i>0)?i-1:p->nVertices-1].x - v->x;
- l.v1.y = p->vertices[(i>0)?i-1:p->nVertices-1].y - v->y;
-
- l.v2 = v2;
-
- if(q == 1 || q == 3) {
- if(!(lineIntersection(&l, &d2, &v2) & INTERSECTION_LINE)) return FALSE;
-
- q2 = quadrant(&v2);
- if(q2 == 0) return TRUE;
-
- if((q == 1 && q2 == 2) || (q == 3 && q2 == 4)) d -= 2;
- else d += 2;
- }
- else {
- if(!(lineIntersection(&l, &d1, &v2) & INTERSECTION_LINE)) return FALSE;
-
- q2 = quadrant(&v2);
- if(q2 == 0) return TRUE;
-
- if((q == 2 && q2 == 3) || (q == 4 && q2 == 1)) d -= 2;
- else d += 2;
- }
- }
- }
-
- return (d == 0) ? FALSE : TRUE;
-}
-
-double polygonPerimeter(const POLYGON *p) {
- int i;
- double d = 0.0;
-
- for(i = 0; i < p->nVertices; i++)
- d += vertexDistance(&p->vertices[i], &p->vertices[(i+1)%p->nVertices]);
-
- return d;
-}
-
-double polygonArea(const POLYGON *p) {
- int i;
- double d = 0.0;
-
- for(i = 0; i < p->nVertices; i++)
- d += (p->vertices[(i+1)%p->nVertices].x+p->vertices[i].x)*(p->vertices[(i+1)%p->nVertices].y-p->vertices[i].y);
-
- return fabs(d/2);
-}
-
-int lineIntersection(const LINE *la, const LINE *lb, VERTEX *v) {
- double xa1 = la->v1.x, ya1 = la->v1.y;
- double xa2 = la->v2.x, ya2 = la->v2.y;
- double xb1 = lb->v1.x, yb1 = lb->v1.y;
- double xb2 = lb->v2.x, yb2 = lb->v2.y;
- double temp;
- int switched = 0;
- VERTEX v2;
-
-
- if(v == NULL) v = &v2;
-
- if(xa1 == xa2 && ya1 == ya2) return INTERSECTION_ERROR;
- if(xb1 == xb2 && yb1 == yb2) return INTERSECTION_ERROR;
-
- if(xa1 == xa2 || xb1 == xb2) {
- temp = xa1; xa1 = ya1; ya1 = temp;
- temp = xa2; xa2 = ya2; ya2 = temp;
- temp = xb1; xb1 = yb1; yb1 = temp;
- temp = xb2; xb2 = yb2; yb2 = temp;
-
- switched = 1;
- }
-
- if(xa1 == xa2 && xb1 == xb2)
- return (xa1 == xb1) ? INTERSECTION_IDENTICAL : INTERSECTION_NONE;
-
- if(xa1 == xa2) {
- v->x = xa1;
- v->y = yb1;
- }
- else if(xb1 == xb2) {
- v->x = xb1;
- v->y = ya1;
- }
- else {
- double ma = (ya2-ya1)/(xa2-xa1);
- double mb = (yb2-yb1)/(xb2-xb1);
- double ba = ya1 - ma*xa1;
- double bb = yb1 - mb*xb1;
-
- if(ma == mb) return (ba == bb) ? INTERSECTION_IDENTICAL : INTERSECTION_NONE;
-
- v->x = (bb-ba)/(ma-mb);
- v->y = ma*v->x + ba;
- }
-
- if(switched) {
- temp = v->x; v->x = v->y; v->y = temp;
-
- //switch back everything for segment tests
- temp = xa1; xa1 = ya1; ya1 = temp;
- temp = xa2; xa2 = ya2; ya2 = temp;
- temp = xb1; xb1 = yb1; yb1 = temp;
- temp = xb2; xb2 = yb2; yb2 = temp;
- }
-
- if(v->x < MIN(xa1,xa2) || v->x > MAX(xa1, xa2) || v->y < MIN(ya1,ya2) || v->y > MAX(ya1, ya2)) {
- if(v->x < MIN(xb1,xb2) || v->x > MAX(xb1, xb2) || v->y < MIN(yb1,yb2) || v->y > MAX(yb1, yb2))
- return INTERSECTION_LINE_LINE;
- else
- return INTERSECTION_LINE_SEGMENT;
- }
- else if(v->x < MIN(xb1,xb2) || v->x > MAX(xb1, xb2) || v->y < MIN(yb1,yb2) || v->y > MAX(yb1, yb2))
- return INTERSECTION_SEGMENT_LINE;
- else
- return INTERSECTION_SEGMENT_SEGMENT;
-}
-
-int lineRectIntersection(const LINE *l, const RECTANGLE *rect, int edge, VERTEX *v) {
- const double minX = rect->x, maxX = rect->x+rect->width;
- const double minY = rect->y, maxY = rect->y+rect->height;
- const LINE top = {{minX, minY}, {maxX, minY}};
- const LINE bottom = {{minX, maxY}, {maxX, maxY}};
- const LINE left = {{minX, minY}, {minX, maxY}};
- const LINE right = {{maxX, minY}, {maxX, maxY}};
-
- if((edge & EDGE_TOP) && (lineIntersection(&top, l, v) == INTERSECTION_SEGMENT_SEGMENT))
- return EDGE_TOP;
- if((edge & EDGE_BOTTOM) && (lineIntersection(&bottom, l, v) == INTERSECTION_SEGMENT_SEGMENT))
- return EDGE_BOTTOM;
- if((edge & EDGE_LEFT) && (lineIntersection(&left, l, v) == INTERSECTION_SEGMENT_SEGMENT))
- return EDGE_LEFT;
- if((edge & EDGE_RIGHT) && (lineIntersection(&right, l, v) == INTERSECTION_SEGMENT_SEGMENT))
- return EDGE_RIGHT;
-
- v->x = v->y = 0;
-
- return EDGE_NONE;
-}
-
-int lineRectIntersections(const LINE *line, const RECTANGLE *rect, int edge, VERTEX *v1, VERTEX *v2) {
- int ret = EDGE_NONE;
-
- ret |= lineRectIntersection(line, rect, edge, v1);
- ret |= lineRectIntersection(line, rect, EDGE_ALL^edge, v2);
-
- return ret;
-}
-
-gboolean linePolygonIntersection(const LINE *l, const POLYGON *p) {
- int i;
- LINE line;
-
- for(i = 0; i < p->nVertices; i++) {
- line.v1 = p->vertices[i];
- line.v2 = p->vertices[(i+1)%p->nVertices];
-
- if(lineIntersection(l, &line, NULL) == INTERSECTION_SEGMENT_SEGMENT)
- return TRUE;
- }
-
- return FALSE;
-}
-
-
-static void edgeVertex(VERTEX *v, int edge, const RECTANGLE *rect) {
- if(edge == EDGE_NONE)
- edge = vertexInRect(v, rect);
-
- if(edge & EDGE_LEFT) v->x = rect->x;
- else if(edge & EDGE_RIGHT) v->x = rect->x+rect->width;
-
- if(edge & EDGE_TOP) v->y = rect->y;
- else if(edge & EDGE_BOTTOM) v->y = rect->y+rect->height;
-}
-
-static int simplifyVertex(VERTEX *v, const VERTEX *to, const RECTANGLE *rect) {
- LINE l = {*v, *to};
- int edge, edge2;
-
-
- edge = vertexInRect(v, rect);
- if(edge == EDGE_NONE) return EDGE_NONE;
-
- edge2 = lineRectIntersection(&l, rect, edge, v);
- if(edge2 != EDGE_NONE) return edge2;
-
- edgeVertex(v, edge, rect);
- return edge;
-}
-
-
-
-static void addSimplifiedLine(const VERTEX *v1, const VERTEX *v2, const RECTANGLE *rect, int last, POLYGON *out) {
- const LINE d1 = {{rect->x, rect->y}, {rect->x+rect->width, rect->y+rect->height}};
- const LINE d2 = {{rect->x, rect->y+rect->height}, {rect->x+rect->width, rect->y}};
-
- LINE l = {*v1, *v2};
- VERTEX v, vi;
- int edge1, edge2;
-
-
- v = *v1;
- if((edge1 = simplifyVertex(&v, v2, rect)) != EDGE_NONE)
- addVertex(out, &v);
-
- v = *v2;
- edge2 = simplifyVertex(&v, v1, rect);
-
- if(edge1 != EDGE_NONE && edge2 != EDGE_NONE && !(edge1 & edge2)) {
- if(lineIntersection(&l, &d1, &vi) == INTERSECTION_SEGMENT_LINE) {
- edgeVertex(&vi, 0, rect);
- addVertex(out, &vi);
- }
- else if(lineIntersection(&l, &d2, &vi) == INTERSECTION_SEGMENT_LINE) {
- edgeVertex(&vi, 0, rect);
- addVertex(out, &vi);
- }
- }
-
- if(!last)
- addVertex(out, &v);
-}
-
-void simplifyPolygon(const POLYGON *in, const RECTANGLE *rect, POLYGON *out) {
- VERTEX v;
- int i;
-
- if(in->nVertices == 0) return;
- else if(in->nVertices == 1) {
- addVertex(out, &in->vertices[0]);
- return;
- }
-
- v = in->vertices[0];
- simplifyVertex(&v, &in->vertices[in->nVertices-1], rect);
- addVertex(out, &v);
-
- for(i = 0; i < in->nVertices; i++) {
- addSimplifiedLine(&in->vertices[i], &in->vertices[(i+1)%in->nVertices], rect, (i == in->nVertices-1), out);
- }
-}
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