2020-08-15 Anuj Verma [sdf -> bsdf] Added a basic overview of the `bsdf' rasterizer. * src/sdf/ftbsdf.c: Added the citation of the original paper and added a overview of the process for generating SDF from bitmaps. 2020-08-15 Anuj Verma [sdf] Added a basic overview of the `sdf' rasterizer. * src/sdf/ftsdf.c: Added the citation of the original paper and added a overview of the process for generating SDF from outlines. * src/sdf/ftsdf.c (sdf_generate_subdivision): Added comment explaining how the optimization works. 2020-08-13 Anuj Verma [sdf] Fix gcc compiler warnings. * src/sdf/ftsdf.c, src/sdf/ftbsdf.c (*): Fix various compiler warnings, which were caused mainly due to unused variables and unused functions. 2020-08-13 Anuj Verma [sdf] Bug fix. * src/sdf/ftsdf.c (sdf_generate_with_overlaps): The outside sign will always be 1. And added a missing `else'. 2020-08-12 Anuj Verma [base] Fix memory leaks due to FreeType internals. * src/base/ftobjs.c (ft_remove_renderer): Similar to `ft_add_renderer', remover raster's `glyph_format' check. Due to this the rasterizers which do not have `glyph_format' of `FT_GLYPH_FORMAT_OUTLINE' won't get deallocated (the `raster_done' function is no called). 2020-08-12 Anuj Verma [sdf] Fix memory leaks. * src/sdf/ftsdf.c (sdf_generate_with_overlaps): Deallocate the temporary bitmaps, and all the rest of the arrays. And also handle the `shape' appropriately so as to not cause memory leaks. 2020-08-12 Anuj Verma [sdf] Handle Post-Script fonts for overlap. * src/sdf/ftsdf.c (sdf_generate_with_overlaps): Handle Handle Post-Script fonts for overlap support. Simply flip the orientation while combining all the separate SDF. Also, handle the `flip_sign' property separately so as to avoid handling extra cases. 2020-08-12 Anuj Verma [sdf] Added overlap support (currently only for TrueType). * src/sdf/ftsdfrend.h (SDF_Renderer_Module): Removed the expermental `optimization' property. Added another property `overlaps', which can be used to turn on the overlap support. * src/sdf/ftsdf.h (SDF_Raster_Params): Ditto as above. * src/sdf/ftsdfrend.c (*): Added functionality to set and get the new `overlaps' property. * src/sdf/ftsdf.c (sdf_raster_render): Removed support for all the optimization modes and only keep the subdivision optimization and the new overlap support function. * src/sdf/ftsdf.c (sdf_generate_coarse_grid): Turned off until we can find a way to make it faster. * src/sdf/ftsdf.c (sdf_generate_with_overlaps): Added a function to generate SDF for shapes with overlapping contours. It basically generate SDF for separate contours in seperate bitmaps and then combine them to remove overlaps. 2020-08-7 Anuj Verma [sdf, bsdf] Added better documentation. * src/sdf/ftsdf.c, src/sdf/ftbsdf.c (*): Added documentation of the structs and enums for both the renderers. 2020-08-6 Anuj Verma [sdf] Added function to get contour orientation. * src/sdf/ftsdf.c (SDF_Contour_Orientation): Added enum to hold the different orientations of a contour. * src/sdf/ftsdf.c (get_contour_orientation): Added function which can be used to compute the orientation of a contour. * src/sdf/ftbsdf.c (*): Remove completed `[TODO]'s. 2020-08-6 Anuj Verma [sdf -> bsdf] Added documentation for functions of the `bsdf' renderer. * src/sdf/ftbsdf.c (*) Added function documentation for function of the `bsdf' renderer. 2020-08-6 Anuj Verma [sdf] Added documentation for function of the `sdf' renderer. * src/sdf/ftsdf.c (*): Added function documentation for function of the `sdf' renderer, and fixed grammar at a few places. 2020-08-5 Anuj Verma [sdf] Added documentation for some structs. * src/sdf/ftsdfrend.h .../ftsdfrend.c .../ftsdfcommon.h .../ftsdf.h : Added documentation for a few structs. 2020-08-5 Anuj Verma [sdf -> bsdf] Extended to work with monochrome bitmaps. * src/sdf/ftbsdf.c (bsdf_init_distance_map): Handle monochrome bitmaps and convert them to the internal intermediate format, which can then be used to generate SDF. 2020-08-3 Anuj Verma * src/sdf/ftsdfrend.c (ft_bsdf_render): Initialize the target bitmap so as to avoid crashes due to uninitialized memory. 2020-08-3 Anuj Verma [sdf -> bsdf] Fixed memory leak. * src/sdf/ftbsdf.c (bsdf_raster_render): Release the allocated distance map. Also, added a log of total memory allocated for generating SDF from bitmap. 2020-08-2 Anuj Verma [sdf -> bsdf] Fixed a bug with `finalize_sdf'. * src/sdf/ftbsdf.c (finalize_sdf): First check if the value is withing [-spread, spread] and then cast it to 6.10 short, otherwise the value can overflow and give negative result. Also, flip the sign if the property `flip_sign' is set to true. 2020-08-1 Anuj Verma [sdf -> bsdf] Added option to use squared distances. * src/sdf/ftbsdf.c (bsdf_is_edge): Modified the function to use distance map rather than the alpha values from the source image. * src/sdf/ftbsdf.c (bsdf_approximate_edge): Only calculate approximate edges for edge pixels. Use `bsdf_is_edge' is to check for edge pixels. For non edge pixel assgn far away distances. * src/sdf/ftbsdf.c (finalize_sdf): Handle distances in case of squared distances. And also use the macro `VECTOR_LENGTH_16D16' in the entire code to compute vector length. This takes care of squared distances. * src/sdf/ftsdfcommon.c (VECTOR_LENGTH_16D16): Move the macro `VECTOR_LENGTH_16D16' from `ftsdf.c' to this file because it is also used by the `bsdf' renderer. 2020-08-1 Anuj Verma * src/sdf/ftbsdf.c (compare_neighbor): Fix bug. 2020-08-1 Anuj Verma [sdf -> bsdf] Optimized a bit. * src/sdf/ftbsdf.c (ED: sign => alpha): Renamed sign to alphas. This is used to store the alpha of the current pixel mapped to the source image. This let's us store additional information without increasing memory usage. * src/sdf/ftbsdf.c (bsdf_init_distance_map): Removed any/all kind of edge approximation and edge check from the function. The function simply copy the source bitmap to the distance map now, preserving alpha values. * src/sdf/ftbsdf.c (compute_edge_distance): Use the new `alpha' parameter to compute gradient and approximate distance. Previously we were using the `dist' variable to store alpha values, which restricts modifying the `dist' variable because we need alpha values of neighbor to compute the gradient. * src/sdf/ftbsdf.c (bsdf_approximate_edge): Now that we can modify the `dist' variable of the distance map, we can combine the two nested loops. * src/sdf/ftbsdf.c (finalize_sdf): Move the `sign' determination and assignment to this function. 2020-07-31 Anuj Verma * src/sdf/ftbsdf.c (compute_edge_distance): Grammer fix. 2020-07-31 Anuj Verma [sdf -> bsdf] Add explanation of the approximation. * src/sdf/ftbsdf.c (compute_gradient => compute_edge_distance): Renamed to make sense of what the function does. Also, added the explanation of the algorithm used and a high level view of how it works. * src/sdf/ftbsdf.c (compare_neighbor): Fix a bug related to value approximation before calling `FT_Vector_Length'. 2020-07-30 Anuj Verma * src/sdf/ftsdfcommon.h (*): Fix line endings. Always use LF line endings. 2020-07-30 Anuj Verma [sdf,bsdf] Put common propertied and functions in one file. * src/sdf/ftsdfcommon.h: Added new file which contains common function, macros, properties for both `sdf' and `bsdf' renderer. * src/sdf/ftsdf.c, src/sdf/ftsdf.h, src/sdf/ftbsdf.c: Remove common properties and include `ftsdfcommon.h'. * src/sdf/rules.mk (SDF_DRV_H): Add the new `ftsdfcommon.h' file to include list. 2020-07-30 Anuj Verma * src/sdf/ftbsdf.c (compute_gradient): Use root(2) for the filter. Also, use the computed gradient to approximate the edge distance from a pixel's position according to the Gustavson's algorithm. 2020-07-29 Anuj Verma [sdf -> bsdf] Added function to approximate edge distance. * src/sdf/ftbsdf.c (bsdf_approximate_edge): The function uses the Gustavson's algorithm to approximate the edge from pixel values. * src/sdf/ftbsdf.c (compute_gradient): The function uses Sobel's operator to compute the gradient at a pixel. The is used to detect edge direction. 2020-07-28 Anuj Verma * src/sdf/ftbsdf.c (_pass): Use function for repetitive task. Use function `compare_neighbor' for comparing the neighbors. Makes it easier to tweak the algorithm and looks better. * src/sdf/ftbsdf.c (compare_neighbor): Added function to compare the neighbors and assign values if the new distance is the shortest. 2020-07-27 Anuj Verma * src/sdf/ftbsdf.c (bsdf_is_edge): Use macros to make it look cleaner. Use `CHECK_NEIGHBOR' macro to check neighbors while finding edges. Make the code more readable and look cleaner. 2020-07-27 Anuj Verma [sdf -> bsdf] Fix edge detection bug. * src/sdf/ftbsdf.c (bsdf_is_edge): [BUG] Check all neighbors including the diagonal neighbors to properly determine the edge. 2020-07-27 Anuj Verma [sdf -> bsdf] Added edge detection algorithm. Added edge detection algorithm. It works by checking the neighboring pixels and if any neighbor is not filled (i.e. belongs to background) we mark the pixel as edge by setting it's distance to 0. * src/sdf/ftbsdf.c (bsdf_is_edge): Added function to detect if the pixel is an edge. 2020-07-27 Anuj Verma [sdf -> bsdf] Added the second pass of the '8SED'. Added the second pass of the 8SED algorithm. The second pass transverse the bitmap from bottom to top and for each row it sweeps forward and backward assigning distances to the grid points. * src/sdf/ftbsdf.c (second_pas): Added function to do the second pass of the 8SED algorithm on the bitmap. 2020-07-26 Anuj Verma [sdf -> bsdf] Optimize the first pass of the 8SED. * src/sdf/ftbsdf.c (first_pass): Optimize the first pass by first approximating the neighbor's distance by adding an offset. The offset will be max root(2) because the maximum be add to a vector is (1, 1). By approximating we can reduce the number of `FT_Vector_Length' calls and thus make the process faster. 2020-07-26 Anuj Verma [sdf] Fix GNU Make build. * src/sdf/rules.mk (SDF_DRV_H): Manually add source files as there is a `ftbsdf.c' file without any `ftbsdf.h'. * src/sdf/ftbsdf.c: Include `fttrigon.h' for `multi' builds. 2020-07-26 Anuj Verma [sdf -> bsdf] Added first pass of the '8SED' algorithm. Added the first pass of the 8SED algorithm. The first pass transverse the bitmap from top to bottom and for each row it sweeps forward and backward assigning distances to the grid points. * src/sdf/ftbsdf.c (ED): Added additional parameter `sign'. * src/sdf/ftbsdf.c (edt8): Added function to convert bitmap to SDF using the 8SED algorithm. * src/sdf/ftbsdf.c (first_pass): Added function to do the first pass of the 8SED algorithm on the bitmap. * src/sdf/ftbsdf.c (finalize_sdf): Added function to assign the final SDF data to the target bitmap. * src/sdf/ftbsdf.c (*): Various minor or experimental changes. * src/sdf/ftsdfrend.c (ft_bsdf_render): Fix spacing. 2020-07-25 Anuj Verma * src/sdf/ftbsdf.c (*): Rename `SDF_TRaster' => `BSDF_TRaster'. `SDF_TRaster' is for the `sdf' renderer. 2020-07-25 Anuj Verma * src/sdf/ftbsdf.c: Typo. `FT_16D16' is 16.16 representation. 2020-07-25 Anuj Verma [sdf -> bsdf renderer] Hold a refrence to `FT_Memory'. Due to the way the 8SED algorithm works we need to keep a track of distances and nearest point of all the pixels/ grid points. * src/sdf/ftbsdf.c (BSDF_TRaster): Added struct to hold the `FT_Memory' reference, to be used to allocate memory. * src/sdf/ftbsdf.c (ED, BSDF_Worker): Added few more essential struct. `ED' contains infomation about the nearest point. `BSDF_Worker' is used to combine all the essentail parameters to functions. * src/sdf/ftbsdf.c (bsdf_copy_source_to_target => bsdf_init_distance_map): Renamed. * src/sdf/ftbsdf.c (*): Various minor changes. * src/sdf/sdf.c: Change the order of source include because `ftsdf.c' change some internal freetype defines which are required in `ftbsdf.c'. 2020-07-25 Anuj Verma [sdf -> bsdf renderer] Convert 8bit bitmap to 16bit. * src/sdf/ftbsdf.c (bsdf_copy_source_to_target): Added extra parameter to flip the bitmap vertically. * src/sdf/ftbsdf.c (bsdf_copy_source_to_target): Implemented functionality to convert 8bits per pixel bitmap to a 16bits per pixel bitmap, which will be used to generate SDF. 2020-07-24 Anuj Verma [sdf] Started the `bsdf' rasterier. * src/sdf/ftbsdf.c (*): Fix line endings. * src/sdf/ftbsdf.c (bsdf_copy_source_to_target): Added function to copy the source bitmap to the center of the target bitmap and also convert it to normalized 16 bits per pixel bitmap. 2020-07-19 Anuj Verma [sdf] Added interface functions for `bsdf' converter. * src/base/ftobjs.c (FT_Render_Glyph_Internal): Remove the bitmap check which prevent calling renderers if the glyph is already a bitmap. The `bsdf' renderer requires a bitmap for conversion. * src/base/ftobjs.c (ft_add_renderer): Remove the glyph format check which ensures that the glyph format for a renderer is `FT_GLYPH_FORMAT_OUTLINE', again the `bsdf' renderer has `FT_GLYPH_FORMAT_BITMAP' as a glyph format, so we need to remove the condition to initialize the renderer properly. * src/sdf/ftbsdf.c (*): Added a rasterizer for the `bsdf' renderer and created necessary functions. * src/sdf/ftbsdf.h: Add forward declaration of the rasterizer. * src/sdf/ftsdfrend.c (ft_bitmap_sdf_renderer_class): Define the new `bsdf' rendere and add the `FT_Renderer_RenderFunc' function, the rest is same as the `sdf' renderer. * src/sdf/ftsdfrend.h: Add forward declaration of the renderer. * src/sdf/rules.mk (SDF_DRV_SRC): Add the new `ftbsdf.c' file to the compile list. * src/sdf/sdf.c: Inclue the `ftbsdf.c' file if making single object. 2020-07-19 Anuj Verma [sdf] Add alloc/free functions. * src/sdf/ftsdf.c (*): Add `sdf_alloc' and `sdf_free' to allocate and deallocate memory respectively. By using function we can directly use them in the conditional statements, which is not possible when using `do {} while ( 0 )'. * src/sdf/ftsdf.c (SDF_MEMORY_TRACKER_): When not debugging don't leave the macros empty otherwise some compiler may emit warning because of empty `;' semi-colon. 2020-07-19 Anuj Verma [sdf] Added new renderer `bsdf'. * src/sdf/ftsdfrend.* (*): Added new renderer named `bsdf' which basically convert bitmap to signed distance fields. This is a part of the `sdf' module and not a separate module on it's own. * src/sdf/module.mk (FTMODULE_H_COMMANDS): Add the new renderer to the list of modules. * include/freetype/config/ftmodule.h: Add the new renderer to default list of modules when not compiling with GNU Make. 2020-07-18 Anuj Verma [sdf] Only track memory in debug mode. * src/sdf/ftsdf.c (*): Disable total memory usage tracking if the program is not in debug mode. 2020-07-18 Anuj Verma [sdfb] Removed Module. Remove sdfb module. Instead of a new module simply create a new renderer in the `sdf' module for converting bitmaps to SDF. 2020-07-18 Anuj Verma [sdfb] Fix GNU Make build. * src/sdfb/rules.mk (SDFB_DRV_H): Fix name of the module specific error file `ftsdfberrs.h'. * src/sdf/ftsdf.h (Optimizations): Fix warning. `warning: comma at end of enumerator list [-Wpedantic]' * src/sdf/ftsdf.c (sdf_generate_coarse_grid): Remove unused variable `cindex', causes warning. `warning: unused variable 'cindex' [-Wunused-variable]' 2020-07-17 Anuj Verma [sdfb] Added new module to generate SDF from bitmap. * src/sdfb/sdfb.c, src/sdfb/ftsdfbrend.c, src/sdfb/ftsdfb.c, src/sdfb/ftsdfbrend.h, src/sdfb/ftsdfb.h, src/sdfb/ftsdfberrs.h: Added files required by the `sdfb' renderer module. * src/sdfb/rules.mk, src/sdfb/module.mk: Added files required to build the `sdfb' module using the default build system. * CMakeLists.txt (BASE_SRCS): Add `src/sdfb/sdfb.c' to the variable. * include/freetype/config/ftmodule.h: Added `sdfb' module declaration so that the module can be compiled when not compiling with GNU make. * modules.cfg (RASTER_MODULES): Include `sdfb' module to the default rasterizer module list. * include/freetype/ftmoderr.h: sdfb module error define * src/sdf/rules.mk: Add EOF. 2020-07-17 Anuj Verma [sdf] Added memory tracker. * src/sdf/ftsdf.c (SDF_MemoryUser): Added struct which is used in place of `FT_Memory::user'. * src/sdf/ftsdf.c (SDF_ALLOC, SDF_FREE): Added macros for allocating and deallocating memory. These macros restore the old `FT_Memory::user' before calling the relevant allocation/deallocation functions so as to not cause errors while debugging memory. And later they add the allocated memory size in a variable. * src/sdf/ftsdf.c (*): Use `SDF_ALLOC', `SDF_FREE' instead of the `FT_' variant. 2020-07-15 Anuj Verma * src/sdf/ftsdfrend.c (sdf_property_set): Minor fix. 2020-07-14 Anuj Verma [sdf] Temporary change. Added new property to dynamically change the optimization to be used to generate the SDF. This can be used to compare the performance of different optimization techniques without going and recompiling the program. And will also be used in the demo to check the performance. 2020-07-13 Anuj Verma [sdf] Added more properties. Added two properties: - `flip_y': To flip the generated SDF along the y axis. - `flip_sign': By default outside is treated to have negative sign, setting `flip_sign' to 1 the outside pixels will have positive sign. * src/sdf/ftsdf.* (*): Use the newly added properties. * src/sdf/ftsdfrend.* (*): Add the newly added properties, and add functionality to set them using `FT_Property_Set'. 2020-07-13 Anuj Verma [sdf] Check for left or right fill. * src/sdf/ftsdf.c (SDF_Params): Added struct which contains some internal data required by the rater- izer (such as left/right fill). * src/sdf/ftsdf.c (sdf_raster_render): Determine the fill side and pass it to the `sdf_generate_' funcs. * src/sdf/ftsdf.c (sdf_generate_): Use the new `SDF_Params' to generate SDF accordingly. 2020-07-12 Anuj Verma [sdf] Optimize the coarse grid optimization. * src/sdf/ftsdf.c (sdf_generate_coarse_grid): Merge the relevant edge finding loop and shortest dist- ance search loop. We can find the relevant edges of a coarse grid and immediately use them to find the shortest distance of the points in the coarse grid. This drastically reduce memory usage and performance. Also, do the sign assignment of the edges which was missing. 2020-07-11 Anuj Verma * src/sdf/ftsdf.c (*): Fixed warnings. Fixed various warnings and other few errors. 2020-07-11 Anuj Verma * src/sdf/ftsdf.c (sdf_generate_coarse_grid): Comments. Add more comments explaining the step by step process of using coarse grid to increase the performance of nearest distance search. 2020-07-11 Anuj Verma * src/sdf/ftsdf.c (sdf_generate_coarse_grid): Memory leak. Release the allocated lists for the coarse grid after we are done using them. 2020-07-11 Anuj Verma [sdf] Completed the coarse grid optimization. * src/sdf/ftsdf.c (sdf_generate_coarse_grid): Fixed an issue with position calculation and upside down images. 2020-07-10 Anuj Verma [sdf] Partially completed the coarse grid optimization. * src/sdf/ftsdf.c (sdf_generate_coarse_grid): Added functionality to check distances of all edges from the coarse grid and add the relevant edges to the list. [Note]: The function is not complete yet. 2020-07-10 Anuj Verma [sdf] Added the coarse grid optimization function. * src/sdf/ftsdf.c (sdf_generate_coarse_grid): The function uses coarse grid to optimize nearest edge search performance. 2020-07-10 Anuj Verma [sdf] Remove use of `FT_List'. Simply use a `next' pointer inside `SDF_Edge' and `SDF_Contour' to create a linked list. This reduces the number of allocations due to `FT_ListNode', also we don't need a doubly linked list. * src/sdf/ftsdf.c (SDF_Edge, SDF_Contour): Remove the `FT_List' and use a `next' pointer to create the linked list. * src/sdf/ftsdf.c(sdf_edge_destructor, sdf_contour_destructor): Removed, not needed any more. * src/sdf/ftsdf.c (*): Remove the use of `FT_List_' functions wherever necessary and sync with the new list. 2020-07-09 Anuj Verma [sdf] Added subdivision optimization. * src/sdf/ftsdf.c (sdf_generate_subdivision): The function generate SDF just like the `sdf_generate' function, but subdivide the curve into a number of lines and then use the `sdf_generate_bounding_box' function to generate SDF. 2020-07-09 Anuj Verma [sdf] Added functions to subdivide a cubic curve. * src/sdf/ftsdf.c (split_cubic, split_sdf_cubic): These functions can be used to subdivide a cubic bezier curve into line segments which can then be used to generate the SDF. * src/sdf/ftsdf.c (split_sdf_shape): Added function to split a cubic into a line segments. * src/sdf/ftsdf.c (sdf_shape_done): No need to pass `FT_Memory' as a parameter, it can be accessed from the `shape' struct. 2020-07-09 Anuj Verma * src/sdf/ftsdf.c (split_sdf_shape): Typo. 2020-07-08 Anuj Verma * src/sdf/ftsdf.c (split_sdf_shape): Memory leak. After recursion the edges variable becomes `NULL' so reassign it to deallocate the list completely. 2020-07-08 Anuj Verma [sdf] Added functions to subdivide a conic curve. * src/sdf/ftsdf.c (split_conic, split_sdf_conic): These functions can be used to subdivide a conic bezier curve into line segments which can then be used to generate the SDF. * src/sdf/ftsdf.c (split_sdf_shape): Added function to split a outline into a line segments. 2020-07-06 Anuj Verma * [GSoC]ChangLog: Fixed typos. 2020-07-06 Anuj Verma * src/sdf/ftsdfrend.c (sdf_generate_bounding_box): Due to the way we use the bounding box, we need to keep a track of signed distances of each pixel so later the sign can be determined properly. The method is certainly faster then checking all the pixels against all the edges, but also require a decent amount of memory to work. 2020-07-06 Anuj Verma [sdf] Precompute the orthogonality. * src/sdf/ftsdf.c (SDF_Signed_Distance): Remove unused fields. * src/sdf/ftsdf.c (resolve_corner): The function can be simplified to a single line. Instead of computing orthogonality here, we precompute it in the corresponding `get_min_distance_' functions more efficiently. * src/sdf/ftsdf.c (get_min_distance_): Precompute orthogonality/ cross product of direction and the distance vector. Since in these function we know that weather the distance vector and the direction are perpendicular, we can simply set the cross to 1 (sin(90) = 1) in case they are perpendicular. This can reduce the number of `FT_Vector_NormLen' calls. 2020-07-05 Anuj Verma [sdf] Added bounding box optimization. * src/sdf/ftsdfrend.c (sdf_generate_bounding_box): The function generate SDF just like the `sdf_generate' function, but uses bounding box to check pixels efficiently. * src/sdf/ftsdfrend.c (get_control_box): Added function to get control box of a `SDF_Edge'. 2020-07-04 Anuj Verma * src/sdf/ftsdfrend.c (sdf_shape_dump): Use `%ld' to printf `signed long' otherwise it gives wrong output. 2020-07-04 Anuj Verma * src/sdf/ftsdfrend.c (ft_sdf_render): Don't negate unsigned integers. 2020-07-03 Anuj Verma * src/sdf/ftsdf.c: Use ASCII single quote (') instead of back tick (`) for derivatives. Looks cleaner. 2020-07-03 Anuj Verma [sdf] Added function to find shortest distance from a point to a cubic bezier. Now the sdf module can render all types of fonts, but still has some issues. * src/sdf/ftsdf.c (get_min_distance_cubic): The function calculates shortest distance from a point to a cubic bezier curve. * src/sdf/ftsdf.c (sdf_edge_get_min_distance): Add the `get_min_distance_cubic' function call. 2020-07-03 Anuj Verma * src/sdf/ftsdf.c (resolve_corner): [Bug] Remove the nearest_point check. Two distances can be same and can give opposite sign, but they may not have a common nearest_point. Also remove distance check because due to precision errors the two distances can be really really close. Therefore use epsilon instead. * src/sdf/ftsdf.c (sdf_contour_get_min_distance): Use epsilon for comparing distances. 2020-07-03 Anuj Verma * src/sdf/ftsdf.c (sdf_shape_dump): Add more info to the debug output. 2020-07-03 Anuj Verma * src/sdf/ftsdf.c (MAX_NEWTON_ITERATION => MAX_NEWTON_DIVISIONS): Renamed to avoid confusion. 2020-07-02 Anuj Verma [sdf] Added Newton's method for shortest distance from a point to a conic. * src/sdf/ftsdf.c (get_min_distance_conic): Created a new function with same name which uses Newton's iteration for finding shortest distance from a point to a conic curve. This doesn't causes underflow. * src/sdf/ftsdf.c (USE_NEWTON_FOR_CONIC): This macro can be used to toggle between Newton or analytical cubic solving method. 2020-07-01 Anuj Verma * src/sdf/ftsdf.c (get_min_distance_conic): Add more details to why we clamp the roots. * src/sdf/ftsdf.c: Make sure preprocessor # is always on the first line. 2020-07-01 Anuj Verma [sdf] Make squared distances toggleable. * src/sdf/ftsdf.c (SDF_Signed_Distance): Renamed squared_distance to distance. It can now represent both squared as well as actual distances. * src/sdf/ftsdf.c (USE_SQUARED_DISTANCES): Added macro which control weather to do computation is squared distances or actual distances. This can be used to avoid overflow when generating large SDF bitmaps. * src/sdf/ftsdf.c: Make sure not to exceed line length of 78. 2020-07-01 Anuj Verma * src/sdf/ftsdf.c (get_min_distance_conic): In case the cubic equation returns zero root, use endpoints for calculating the shortest distance. 2020-07-01 Anuj Verma [sdf] Added function to find shortest distance from a point to a conic bezier. Now the sdf module can render ttf fonts or fonts with line and conic segments. * src/sdf/ftsdf.c (get_min_distance_conic): The function calculates shortest distance from a point to a conic bezier curve. * src/sdf/ftsdf.c (sdf_edge_get_min_distance): Add the `get_min_distance_conic' function call. 2020-07-01 Anuj Verma * src/sdf/ftsdf.c (get_min_distance_line): First check pointer before using or dereferencing them. 2020-06-30 Anuj Verma * src/sdf/ftsdf.c: Avoid parentheses if there is only one statement inside a control-flow statement. 2020-06-30 Anuj Verma [sdf] Added functions to solve polynomial equations. * src/sdf/ftsdf.c (solve_quadratic_equation, solve_cubic_equation): Added functions to solve quadratic and cubic equations. These will be used for conic bezier curves only. 2020-06-30 Anuj Verma * src/sdf/ftsdf.c (square_root, cube_root, arc_cos): Use FT_16D16 instead of FT_Fixed to avoid confusion. 2020-06-30 Anuj Verma * src/sdf/ftsdf.c (cube_root, arc_cos): Added a few essential math functions. 2020-06-30 Anuj Verma [sdf] Fixed compilation under gnumake. * src/sdf/rules.mk (DRV_OBJ_ => DRV_OBJS_): Fixed variable name so that the sdf can compile. * src/sdf/module.mk: Fixed spacing. * src/sdf/*.c: Fixed all compiler warnings. * [GSoC]ChangLog: Fixed dates. 2020-06-29 Anuj Verma [sdf] Added function to resolve corners in case of ambiguity. * src/sdf/ftsdf.c (resolve_corner): Added function to determine the correct sign in case there are two sign for the same shortest distance (happens around corners). * src/sdf/ftsdf.c: Typo neartest_point -> nearest_point. 2020-06-29 Anuj Verma [sdf] The module can now generate signed distance fields for outline with only lines. * src/sdf/ftsdf.c (get_min_distance_line): Calculation mistake. * src/sdf/ftsdf.c (square_root): Added function to calculate square root of a 16.16 fixed point integer. * src/sdf/ftsdf.c (sdf_generate): Assign values to the output bitmap, currently the output is 6.10 fixed point which can contain values from [-32, 32]. Also fixed a bug which was causing upside down images. * src/sdf/ftsdfrend.c (ft_sdf_render): Fixed alignment issues. 2020-06-28 Anuj Verma [sdf] Added function to find shortest distance from a point to a line. * src/sdf/ftsdf.c (get_min_distance_line): The function calculate the shortest signed distance from a point to a line segment. * src/sdf/ftsdf.c (sdf_contour_get_min_distance): Typo. * src/sdf/ftsdf.c (SDF_Signed_Distance): Use squared distance instead of actual distance for performance. 2020-06-28 Anuj Verma * src/sdf/ftsdf.c (SDF_Iterator_IO): Removed. * src/sdf/ftsdf.c (sdf_edge_iterator_func => sdf_edge_get_min_distance sdf_contour_iterator_func => sdf_contour_get_min_distance): Renamed. Manually iterate through the lists instead of `FT_List_Iterate' to avoid io structs and looks a bit cleaner. 2020-06-28 Anuj Verma [sdf] Added basic outline of the functions required to generate sdf. * src/sdf/ftsdf.c (SDF_Signed_Distance): Added struct which represent a complete signed distance and can be used to get cross, dot, sign etc. * src/sdf/ftsdf.c (SDF_Iterator_IO): This struct will be used while `FT_List_Iterate'. * src/sdf/ftsdf.c (sdf_generate): Added function which generate SDF from `SDF_Shape'. * src/sdf/ftsdf.c (sdf_edge_iterator_func, sdf_contour_iterator_func): Added functions which iterate through contours and edges and return the shortest distance. 2020-06-27 Anuj Verma [sdf] Added `SDF_Raster_Params' struct which extends `FT_Raster_Params' and has a few extra fields. This is done to pass extra data to the sdf rasterizer which is required while rasterizing. * src/sdf/ftsdf.h (SDF_Raster_Params): Added a struct which extends `FT_Raster_Params' and has the `spread' parameter. Also moved the max, min and default spread values to this header file. * src/sdf/ftsdf.c (sdf_raster_render): Added parameter and attribute checking in order to pick errors and return early. * src//sdf/ftsdfrend.c (ft_sdf_render): Setup the `SDF_Raster_Params' and pass it to the rasterizer instead of `FT_Raster_Params'. 2020-06-27 Anuj Verma * include/freetype/ftimage.h (FT_RASTER_FLAG_): Added a new raster flag `FT_RASTER_FLAG_SDF'. The `ftsdf' rasterizer will only render if this flag is set. * src/sdf/ftsdfrend.c (ft_sdf_render): Set the `flags' field of `FT_Raster_Params' to `FT_RASTER_FLAG_SDF'. 2020-06-26 Anuj Verma * src/sdf/ftsdf.c (sdf_shape_dump): Use `FT_TRACEX' instead of `printf'. 2020-06-26 Anuj Verma * src/sdf/ftsdf.c (sdf_shape_dump): Added function to dump the `SDF_Shape' on the console for debugging. 2020-06-26 Anuj Verma [sdf] Added functions to de-allocate `SDF_' structs. * src/sdf/ftsdf.c (SDF_Contour, SDF_Shape): Use `FT_ListRec' instead of `FT_List' to avoid a few extra allocations. * src/sdf/ftsdf.c (SDF_Edge, SDF_Contour, SDF_Shape): Added functions to de-allocate these structs and their members. * src/sdf/ftsdfrenc.c: Typo. 2020-06-25 Anuj Verma [sdf] Decompose outline and store it in a temporary `SDF_Shape' object for easy iteration and pre-computing some variables. * src/sdf/ftsdf.c (sdf_outline_decompose): Added function to decompost outline and store it in a `SDF_Shape' object. This allows us to pre-compute some variable. 2020-06-25 Anuj Verma [sdf] Added essential enums and structs required. * src/freetype/internal/fttrace.h: Remove tabs. * src/sdf/ftsdfrend.c (ft_sdf_render): Calculate padding using the `spread'. * src/sdf/ftsdf.c (SDF_Edge_Type, SDF_Edge, SDF_Contour, SDF_Shape): Added structures and their initializer functions. 2020-06-23 Anuj Verma [sdf] Added functionality to set and get module properties. Also added a `spread' property. * src/freetype/internal/fttrace.h: Added sdf module trace define. * src/sdf/ftsdf.c (sdf_TRaster => SDF_TRaster): Use capital character for structs. * src/sdf/ftsdfrend.h (SDF_Renderer_Module): Added a struct which extends the `FT_RendererRec' and added the `spread' property. * src/sdf/ftsdfrend.c: Synchronized the code to use the new `SDF_Renderer_Module' and added functions to get/set the properties. 2020-06-20 Anuj Verma [sdf] Implemented a few functions required by a renderer module. * src/sdf/ftsdf.c (sdf_TRaster_): Added new structure to hold the memory allocator `FT_Memory'. * src/sdf/ftsdf.c (ft_sdf_raster): Implemented a few essential functions required by `FT_Raster'. * src/sdf/ftsdfrend.c (ft_sdf_renderer_class): Implemented a few essential functions required by `FT_Renderer'. * src/sdf/ftsdfrend.c (ft_sdf_render): Added functionality to compute shift and padding before rendering the outline. 2020-06-19 Anuj Verma * include/freetype/ftimage.h (FT_Render_Mode_): Added new pixel mode `FT_PIXEL_MODE_GRAY16' which will be used to represent signed values while rendering to SDF bitmap. 2020-06-19 Anuj Verma * include/freetype/freetype.h (FT_Render_Mode_): Added new rendermode `FT_RENDER_MODE_SDF' which will be used by the `sdf' module to generate signed distance fields from glyph's outline. * src/sdf/ftsdfrend.h, src/sdf/module.mk, src/sdf/rules.mk: Add a new line at the end of files. 2020-06-18 Anuj Verma [sdf] Added the structure of a new module to render signed distance fields. * src/sdf/sdf.c, src/sdf/ftsdfrend.c, src/sdf/ftsdf.c, src/sdf/ftsdfrend.h, src/sdf/ftsdf.h, src/sdf/ftsdferrs.h: Added files required by the `sdf' renderer module and added the basic structure and functions required. * src/sdf/rules.mk, src/sdf/module.mk: Added files required to build the `sdf' module using the default build system. * CMakeLists.txt (BASE_SRCS): Add `src/sdf/sdf.c' to the variable. * include/freetype/config/ftmodule.h: Added `sdf' module declaration so that the module can be compiled when not compiling with GNU make. * modules.cfg (RASTER_MODULES): Include `sdf' module to the default rasterizer module list. * include/freetype/ftmoderr.h: sdf module error define