From ff04f157cec57e3a19a7078040e1d9604812d32c Mon Sep 17 00:00:00 2001
From: Matthias Kramm <kramm@quiss.org>
Date: Thu, 10 Sep 2009 14:25:16 +0200
Subject: [PATCH] small polygon refinement
---
lib/gfxpoly/convert.c | 49 ++++++++++++++++++++++++++++++++++++++-----------
lib/gfxpoly/convert.h | 1 +
2 files changed, 39 insertions(+), 11 deletions(-)
diff --git a/lib/gfxpoly/convert.c b/lib/gfxpoly/convert.c
index dae58b6..39517d7 100644
--- a/lib/gfxpoly/convert.c
+++ b/lib/gfxpoly/convert.c
@@ -175,9 +175,8 @@ static void compactlineto(polywriter_t*w, int32_t x, int32_t y)
if(p.x == data->last.x && p.y == data->last.y)
return;
- if(p.y < data->last.y && data->dir != DIR_UP ||
- p.y > data->last.y && data->dir != DIR_DOWN ||
- data->new) {
+ if((p.y < data->last.y && data->dir != DIR_UP) ||
+ (p.y > data->last.y && data->dir != DIR_DOWN) || data->new) {
finish_segment(data);
data->dir = p.y > data->last.y ? DIR_DOWN : DIR_UP;
data->points[0] = data->last;
@@ -407,7 +406,7 @@ gfxline_t*gfxline_from_gfxpoly(gfxpoly_t*poly)
}
#endif
-gfxline_t*gfxline_from_gfxpoly(gfxpoly_t*poly)
+static gfxline_t*mkgfxline(gfxpoly_t*poly, char preserve_direction)
{
gfxpolystroke_t*stroke;
int count = 0;
@@ -416,6 +415,7 @@ gfxline_t*gfxline_from_gfxpoly(gfxpoly_t*poly)
dict_t*d = dict_new2(&point_type);
dict_t*todo = dict_new2(&ptr_type);
gfxpolystroke_t*stroke_min= poly->strokes;
+ int32_t x_min=stroke_min->points[0].x;
int32_t y_min=stroke_min->points[0].y;
for(stroke=poly->strokes;stroke;stroke=stroke->next) {
dict_put(todo, stroke, stroke);
@@ -423,10 +423,15 @@ gfxline_t*gfxline_from_gfxpoly(gfxpoly_t*poly)
count += stroke->num_points;
if(stroke->dir == DIR_UP) {
dict_put(d, &stroke->points[stroke->num_points-1], stroke);
+ if(!preserve_direction)
+ dict_put(d, &stroke->points[0], stroke);
} else {
dict_put(d, &stroke->points[0], stroke);
+ if(!preserve_direction)
+ dict_put(d, &stroke->points[stroke->num_points-1], stroke);
}
- if(stroke->points[0].y < y_min) {
+ if(stroke->points[0].y < y_min ||
+ (stroke->points[0].y == y_min && stroke->points[0].x < x_min)) {
y_min = stroke->points[0].y;
stroke_min = stroke;
}
@@ -439,17 +444,29 @@ gfxline_t*gfxline_from_gfxpoly(gfxpoly_t*poly)
point_t last = {INVALID_COORD, INVALID_COORD};
char should_connect = 0;
while(stroke) {
+ if(stroke && !preserve_direction) {
+ char del1 = dict_del2(d, &stroke->points[0], stroke);
+ char del2 = dict_del2(d, &stroke->points[stroke->num_points-1], stroke);
+ assert(del1 && del2);
+ }
assert(dict_contains(todo, stroke));
int t;
int pos = 0;
int incr = 1;
- if(stroke->dir == DIR_UP) {
- pos = stroke->num_points-1;
- incr = -1;
+ if(preserve_direction) {
+ if(stroke->dir == DIR_UP) {
+ pos = stroke->num_points-1;
+ incr = -1;
+ }
+ } else {
+ // try to find matching point on either end.
+ // Prefer downward.
+ if(last.x == stroke->points[stroke->num_points-1].x &&
+ last.y == stroke->points[stroke->num_points-1].y) {
+ pos = stroke->num_points-1;
+ incr = -1;
+ }
}
- /* TODO: keeping the up/down order intact increases the polygon size
- considerably. If this is going to be an even/odd polygon,
- we could ignore it and save some space */
if(last.x != stroke->points[pos].x || last.y != stroke->points[pos].y) {
l[count].x = stroke->points[pos].x * poly->gridsize;
l[count].y = stroke->points[pos].y * poly->gridsize;
@@ -491,6 +508,16 @@ gfxline_t*gfxline_from_gfxpoly(gfxpoly_t*poly)
return l;
}
+gfxline_t*gfxline_from_gfxpoly(gfxpoly_t*poly)
+{
+ return mkgfxline(poly, 0);
+}
+
+gfxline_t*gfxline_from_gfxpoly_updown(gfxpoly_t*poly)
+{
+ return mkgfxline(poly, 1);
+}
+
static windcontext_t onepolygon = {1};
gfxline_t* gfxpoly_circular_to_evenodd(gfxline_t*line, double gridsize)
{
diff --git a/lib/gfxpoly/convert.h b/lib/gfxpoly/convert.h
index f0a8fb9..7c18958 100644
--- a/lib/gfxpoly/convert.h
+++ b/lib/gfxpoly/convert.h
@@ -22,6 +22,7 @@ gfxpoly_t* gfxpoly_from_file(const char*filename, double gridsize);
void gfxpoly_destroy(gfxpoly_t*poly);
gfxline_t*gfxline_from_gfxpoly(gfxpoly_t*poly);
+gfxline_t*gfxline_from_gfxpoly_updown(gfxpoly_t*poly); // preserves up/down
gfxline_t* gfxpoly_circular_to_evenodd(gfxline_t*line, double gridsize);
gfxpoly_t* gfxpoly_createbox(double x1, double y1,double x2, double y2, double gridsize);
--
1.7.10.4