Added viewBox and unit coversion support

- added exact bounds calculation for bezier curves, paths, shapes
- added unit coversion for svg length values (use px internally)
- added viewBox and preserveAspectRatio handling
- removed some test SVGs

1 files changed, 18 insertions, 2 deletions

diff --git a/README.md b/README.md
index e68c5a9..9aa9a3f 100644
--- a/README.md
+++ b/README.md
@@ -9,7 +9,18 @@ NanoSVG is a simple stupid single-header-file SVG parse. The output of the parse
 
 The library suits well for anything from rendering scalable icons in your editor application to prototyping a game.
 
-NanoSVG supports a wide range of SVG features, if somehing is missing, feel free to create a pull request!
+NanoSVG supports a wide range of SVG features, but something may be missing, feel free to create a pull request!
+
+The shapes in the SVG images are transformed by the viewBox and converted to specified units.
+That is, you should get the same looking data as your designed in your favorite app.
+
+NanoSVG can return the paths in few different units. For example if you want to render an image, you may choose
+to get the paths in pixels, or if you are feeding the data into a CNC-cutter, you may want to use millimeters. 
+
+The units passed to NanoVG should be one of: 'px', 'pt', 'pc' 'mm', 'cm', or 'in'.
+DPI (dots-per-inch) controls how the unit conversion is done.
+
+If you don't know or care about the units stuff, "px" and 96 should get you going.
 
 ## Rasterizer
 
@@ -25,7 +36,7 @@ The intended usage for the rasterizer is to for example bake icons of different
 ``` C
 // Load
 struct NSVGimage* image;
-image = nsvgParseFromFile("test.svg.");
+image = nsvgParseFromFile("test.svg", "px", 96);
 printf("size: %f x %f\n", image->width, image->height);
 // Use...
 for (shape = image->shapes; shape != NULL; shape = shape->next) {
@@ -44,8 +55,11 @@ nsvgDelete(image);
 
 In order to use NanoSVG in your own project, just copy nanosvg.h to your project.
 In one C/C++ define `NANOSVG_IMPLEMENTATION` before including the library to expand the NanoSVG implementation in that file.
+NanoSVG depends on `stdio.h` and `math.h`, they should be included where the implementation is expanded before including NanoSVG. 
 
 ``` C
+#include <stdio.h>
+#include <math.h>
 #define NANOSVG_IMPLEMENTATION	// Expands implementation
 #include "nanosvg.h"
 ```
@@ -53,6 +67,8 @@ In one C/C++ define `NANOSVG_IMPLEMENTATION` before including the library to exp
 By default, NanoSVG parses only the most common colors. In order to get support for full list of [SVG color keywords](http://www.w3.org/TR/SVG11/types.html#ColorKeywords), define `NANOSVG_ALL_COLOR_KEYWORDS` before expanding the implementation.
 
 ``` C
+#include <stdio.h>
+#include <math.h>
 #define NANOSVG_ALL_COLOR_KEYWORDS	// Include full list of color keywords.
 #define NANOSVG_IMPLEMENTATION		// Expands implementation
 #include "nanosvg.h"