Add tol parameter to remove flattening tolerance constant (#16)

Remove `LATTENING_TOLERANCE` const and add `tol` parameter down from `parse()`.

- Update the ffi wrapper
- Tests are using the old const value

Closes #3.

svg2polylines-ffi/example.c

@@ -25,7 +25,7 @@ typedef struct Polyline {
     size_t len;
 } Polyline;
 
-uint8_t svg_str_to_polylines(char* svg, Polyline** polylines, size_t* polylines_len);
+uint8_t svg_str_to_polylines(char* svg, double tol, Polyline** polylines, size_t* polylines_len);
 void free_polylines(Polyline* polylines, size_t polylines_len);
 
 
@@ -53,7 +53,7 @@ int main() {
     size_t polylines_len = 0;
 
     // Process data
-    uint8_t err = svg_str_to_polylines(input, &polylines, &polylines_len);
+    uint8_t err = svg_str_to_polylines(input, 0.15, &polylines, &polylines_len);
 
     // Error handling
     if (err > 0) {

svg2polylines-ffi/example.py

@@ -14,7 +14,7 @@
     size_t len;
 } Polyline;
 
-uint8_t svg_str_to_polylines(char* svg, Polyline** polylines, size_t* polylines_len);
+uint8_t svg_str_to_polylines(char* svg, double tol, Polyline** polylines, size_t* polylines_len);
 void free_polylines(Polyline* polylines, size_t polylines_len);
 ''')
 
@@ -47,7 +47,7 @@ def print_polyline(p):
 
 polylines = ffi.new('Polyline**')
 polylines_len = ffi.new('size_t*')
-lib.svg_str_to_polylines(svg_input, polylines, polylines_len)
+lib.svg_str_to_polylines(svg_input, 0.15, polylines, polylines_len)
 
 
 print('Found %d polylines!' % polylines_len[0])

svg2polylines-ffi/src/lib.rs

@@ -3,7 +3,7 @@
 use std::ffi::CStr;
 use std::mem;
 
-use libc::{c_char, size_t};
+use libc::{c_char, c_double, size_t};
 use svg2polylines::{parse, CoordinatePair};
 
 /// Structure that contains a pointer to the coordinate pairs as well as the
@@ -37,6 +37,7 @@ pub struct Polyline {
 #[no_mangle]
 pub unsafe extern "C" fn svg_str_to_polylines(
     svg: *const c_char,
+    tol: c_double,
     polylines: *mut *mut Polyline,
     polylines_len: *mut size_t,
 ) -> u8 {
@@ -48,7 +49,7 @@ pub unsafe extern "C" fn svg_str_to_polylines(
     let r_str = c_str.to_str().unwrap();
 
     // Process
-    match parse(r_str) {
+    match parse(r_str, tol) {
         Ok(vec) => {
             // Convert `Vec<Vec<CoordinatePair>>` to `Vec<Polyline>`
             let mut tmp_vec: Vec<Polyline> = vec

svg2polylines/examples/basic.rs

@@ -25,7 +25,7 @@ fn main() {
     file.read_to_string(&mut s).unwrap();
 
     // Parse data
-    let polylines: Vec<Polyline> = svg2polylines::parse(&s).unwrap_or_else(|e| {
+    let polylines: Vec<Polyline> = svg2polylines::parse(&s, 0.15).unwrap_or_else(|e| {
         println!("Error: {}", e);
         exit(2);
     });

svg2polylines/examples/preview.rs

@@ -30,7 +30,7 @@ fn main() {
     file.read_to_string(&mut s).unwrap();
 
     // Parse data
-    let polylines: Vec<Polyline> = svg2polylines::parse(&s).unwrap_or_else(|e| {
+    let polylines: Vec<Polyline> = svg2polylines::parse(&s, 0.15).unwrap_or_else(|e| {
         println!("Error: {}", e);
         exit(2);
     });