* src/sdf/ftsdf.c (*): Added a technical overview of the working of the `sdf' rasterizer.
* src/sdf/ftbsdf,c (*) : Added a technical overview of the working of the `bsdf'
rasterizer.
* src/sdf/ftsdf.c (bsdf_raster_): Added interface functions which are called from the
FreeType core library to rasterize and do various other stuff with the rasterizer.
* src/sdf/ftbsdf.c (finalize_sdf): The function uses the final data present in the
distance map and copies is to the output bitmap. It also converts our data into the
desired format.
* src/sdf/ftbsdf.c (edt8): Added function to do the euclidean transform to the
distance map. The function basically does the 8SED algorithm on the distance map
to compute the distance transform of the bitmap.
* src/sdf/ftbsdf.c (first_pass, second_pass): The first and the second pass of the 8SED
algorithm.
* src/sdf/ftbsdf.c (compare_neighbor): Helper function to compare the neighbor of
a pixel which is required in the 8SED algorithm.
* src/sdf/ftbsdf.c (bsdf_init_distance_map): The function copies the source bitmap to
the intermediate distance map which is present within the `worker'.
* src/sdf/ftbsdf.c (compute_edge_distance): Added function to approximate edges
given only the array of alpha values representing pixel coverage. This function uses
the Gustavson's algorithm for approximating.
* src/sdf/ftbsdf.c (bsdf_approximate_edge): This function loops through the entire
bitmap and for edge pixel (found using `bsdf_is_edge') compute approximate edge
distances (using `compute_edge_distance').
* src/sdf/ftbsdf.c (bsdf_is_edge): The function find the edge pixel in a distance map
which is basically a 2D array of alpha values which represent coverage in the
original input bitmap.
* src/sdf/ftbsdf.c (*): Added all the essential structures required internally by the
`bsdf' rasterizer as well as the initializer for the `ED' struct.
Added the necessary files required by the `sdf' module. These include files
for both the `sdf' and the `bsdf' renderers. Here is breakdown of what the
specific files will contain:
* src/sdf/ftsdfrend.*: Both the renderers.
* src/sdf/ftsdf.*: The rasterizer for the `sdf' renderer.
* src/sdf/ftbsdf.c: The rasterizer for the `bsdf' renderer.
* src/sdf/ftsdfcommon.h: Commmon properties and functions for both the
rasterizers.
* src/sdf/ftsdferrs.h: Common error define.
* src/sdf/sdf.c: For building a single object of the entire module.
Anuj Verma