% File: hawkdraw-shadings.code.tex % Copyright 2026 Jasper Habicht (mail(at)jasperhabicht.de). % % This work may be distributed and/or modified under the % conditions of the LaTeX Project Public License version 1.3c, % available at http://www.latex-project.org/lppl/. % % This file is part of the `hawkdraw' package (The Work in LPPL) % and all files in that bundle must be distributed together. % % This work has the LPPL maintenance status `maintained'. % % BOF % v0.9.0 2026-09-07 % ===== % Shadings % === % PDF treats shadings as patterns and hence as color that can be used to fill or stroke a path. There are % various types of shadings, but we only define linear, radial and conic shaings here as type 2, 3 and 6 % shadings respectively. % Since we want shadings to be reusable, we define them as PDF objects with a size of 100bp times 100bp. % Type 2 and 3 shadings are defined by functions, type 6 shadings are defined by a binary stream. % Every shading defined by its type, the used colors and whether or not it has some offset (for radial or % conic shadings) is defined separatey as PDF Object. In the PDF, two objects are created for every use of % a shading, one that defines the shading using functions and one as that defines a pattern representing a % scaled box referring to the shading. % In order to allow for rotation of shadings, we use the PGF approach of scaling the shadings to twice % the size of the path they should apply to. Thus, we need to use multiple functions to define linear % shadings, because the outer part of the shading object will be clipped away by the path. We do this by % defining the functions in a nested way. The outer function is a type 3 function which defines the inner % functions. The inner functions depend on the type of the shading and the number of colors used. % For proper positioning of shadings without the need to retrieve the current position of the path via two % compilation runs it is necessary to place the shading inside a PDF XObject which creates a proper % coordinate system. % === \msg_new:nnn { hawkdraw } { shading-unknown } { Shading ~ `#1` ~ unknown. } \int_new:N \g__hawkdraw_shading_id_int \int_new:N \g__hawkdraw_shading_obj_int \box_new:N \l__hawkdraw_shading_box \clist_new:N \l_hawkdraw_shading_path_use_clist \clist_new:N \l_hawkdraw_shading_colors_clist \fp_new:N \l_hawkdraw_shading_rotate_fp \fp_new:N \l_hawkdraw_shading_offset_fp \bool_new:N \l_hawkdraw_shading_circular_bool \fp_new:N \l_hawkdraw_shading_angle_delta_fp \dim_new:N \l__hawkdraw_shading_path_linewidth_dim \dim_new:N \l__hawkdraw_shading_bb_xmin_dim \dim_new:N \l__hawkdraw_shading_bb_xmax_dim \dim_new:N \l__hawkdraw_shading_bb_ymin_dim \dim_new:N \l__hawkdraw_shading_bb_ymax_dim \dim_new:N \l__hawkdraw_shading_bb_xmin_o_dim \dim_new:N \l__hawkdraw_shading_bb_xmax_o_dim \dim_new:N \l__hawkdraw_shading_bb_ymin_o_dim \dim_new:N \l__hawkdraw_shading_bb_ymax_o_dim \dim_new:N \l__hawkdraw_shading_xoffset_dim \dim_new:N \l__hawkdraw_shading_yoffset_dim \fp_new:N \l__hawkdraw_shading_origin_fp \exp_args_generate:n { NVVVV } % Storing the path options for later use in the shading XObject \tl_new:N \l__hawkdraw_shading_path_options_tl \hook_gput_code:nnn { hawkdraw / options / before } { hawkdraw / shading } { \tl_set_eq:NN \l__hawkdraw_shading_path_options_tl \l__hawkdraw_path_options_tl } \keys_define:nn { hawkdraw / path } { shading .code:n = { \int_gincr:N \g__hawkdraw_shading_id_int \tl_put_right:Nn \l_hawkdraw_path_preactions_tl { \dim_set:Nn \l__hawkdraw_shading_xoffset_dim { \dim_min:nn { \hawkdraw_tuple_use_i:n { \g_hawkdraw_path_point_first_fp } } { \hawkdraw_path_bb_xmin: } } \dim_set:Nn \l__hawkdraw_shading_yoffset_dim { \dim_min:nn { \hawkdraw_tuple_use_ii:n { \g_hawkdraw_path_point_first_fp } } { \hawkdraw_path_bb_ymin: } } \pdfxform_new:enn { hawkdraw_shading_ \int_use:N \g__hawkdraw_shading_id_int } { } { \draw_suspend_begin: \draw_begin: \tl_set_eq:NN \l__hawkdraw_path_options_tl \l__hawkdraw_shading_path_options_tl \hawkdraw_path_set_options: \tl_trim_spaces_apply:nN { \g_hawkdraw_softpath_original_tl } \__hawkdraw_path_process:o \draw_transform_shift:n { ( - \l__hawkdraw_shading_xoffset_dim , - \l__hawkdraw_shading_yoffset_dim ) } \tl_use:N \g_hawkdraw_softpath_original_tl \dim_set_eq:NN \l__hawkdraw_shading_bb_xmin_dim \g_draw_bb_xmin_dim \dim_set_eq:NN \l__hawkdraw_shading_bb_xmax_dim \g_draw_bb_xmax_dim \dim_set_eq:NN \l__hawkdraw_shading_bb_ymin_dim \g_draw_bb_ymin_dim \dim_set_eq:NN \l__hawkdraw_shading_bb_ymax_dim \g_draw_bb_ymax_dim \hawkdraw_shading_use:n {#1} \draw_path_use_clear:e { \clist_use:N \l_hawkdraw_shading_path_use_clist } \draw_end: \draw_suspend_end: } \hbox_set:Nn \l__hawkdraw_shading_box { \pdfxform_use:e { hawkdraw_shading_ \int_use:N \g__hawkdraw_shading_id_int } } \clist_if_in:NnTF \l_hawkdraw_shading_path_use_clist { stroke } { \fp_set:Nn \l__hawkdraw_shading_origin_fp { -0.5 * \l_hawkdraw_path_linewidth_dim , \fp_if_nan:nTF { \l_hawkdraw_picture_baseline_fp } { -0.5 * \l_hawkdraw_path_linewidth_dim } { \l_hawkdraw_picture_baseline_fp } } } { \fp_set:Nn \l__hawkdraw_shading_origin_fp { 0pt , 0pt } } \draw_box_use:Nn \l__hawkdraw_shading_box { ( \l__hawkdraw_shading_xoffset_dim , \l__hawkdraw_shading_yoffset_dim ) + \l__hawkdraw_shading_origin_fp } \bool_gset_false:N \g__hawkdraw_path_use_clip_bool } } , shading ~ colors .clist_set:N = \l_hawkdraw_shading_colors_clist , shading ~ rotate .fp_set:N = \l_hawkdraw_shading_rotate_fp , shading ~ rotate .initial:n = { 0.0 } , shading ~ offset .fp_set:N = \l_hawkdraw_shading_offset_fp , shading ~ offset .initial:n = { 0.0 } , shading ~ circular .bool_set:N = \l_hawkdraw_shading_circular_bool , shading ~ circular .default:n = { true } , shading ~ circular .initial:n = { false } , shading ~ angle ~ delta .fp_set:N = \l_hawkdraw_shading_angle_delta_fp , shading ~ angle ~ delta .initial:n = { 360 } , shading ~ type .code:n = { \clist_set:Nn \l_hawkdraw_shading_path_use_clist {#1} }, shading ~ type .initial:n = { fill } , } \keys_define:nn { hawkdraw / path / node } { shading .code:n = { \int_gincr:N \g__hawkdraw_shading_id_int \tl_put_right:Nn \l_hawkdraw_node_postactions_tl { \pdfxform_new:enn { hawkdraw_shading_ \int_use:N \g__hawkdraw_shading_id_int } { } { \draw_suspend_begin: \draw_begin: \tl_set_eq:NN \l__hawkdraw_path_options_tl \l__hawkdraw_shading_path_options_tl \hawkdraw_path_set_options: \draw_transform_shift:n { ( 0.5 * \l_hawkdraw_node_natural_width_dim , 0.5 * \l_hawkdraw_node_natural_height_dim ) } \tl_use:N \l__hawkdraw_node_frame_path_tl \dim_set_eq:NN \l__hawkdraw_shading_bb_xmin_dim \g_draw_bb_xmin_dim \dim_set_eq:NN \l__hawkdraw_shading_bb_xmax_dim \g_draw_bb_xmax_dim \dim_set_eq:NN \l__hawkdraw_shading_bb_ymin_dim \g_draw_bb_ymin_dim \dim_set_eq:NN \l__hawkdraw_shading_bb_ymax_dim \g_draw_bb_ymax_dim \hawkdraw_shading_use:n {#1} \draw_path_use:e { \clist_use:N \l_hawkdraw_shading_path_use_clist } \draw_end: \draw_suspend_end: } \hbox_set:Nn \l__hawkdraw_shading_box { \pdfxform_use:e { hawkdraw_shading_ \int_use:N \g__hawkdraw_shading_id_int } \bool_gset_false:N \g__hawkdraw_path_use_clip_bool } \draw_box_use:Nn \l__hawkdraw_shading_box { ( -0.5 * \l_hawkdraw_node_natural_width_dim , -0.5 * \l_hawkdraw_node_natural_height_dim ) } } } , } \tl_new:N \l__hawkdraw_shading_color_value_tmp_tl \seq_new:N \l__hawkdraw_shading_color_values_seq \cs_generate_variant:Nn \color_export:nnN { e } \cs_new_protected:Npn \hawkdraw_shading_set:nnn #1#2#3 { \pdf_object_new:n { hawkdraw_shading_ #1 } \tl_if_empty:nTF {#3} { \pdf_object_write:nne { hawkdraw_shading_ #1 } { dict } {#2} } { \hawkdraw_support_pdf_write_stream:nee { hawkdraw_shading_ #1 } {#2} {#3} } \tl_const:ce { c__hawkdraw_shading_ #1 _tl } { \pdf_object_ref:n { hawkdraw_shading_ #1 } } } \cs_generate_variant:Nn \hawkdraw_shading_set:nnn { e } \cs_new_protected:Npn \hawkdraw_shading_use:n #1 { \hawkdraw_shading_create:nV {#1} \l_hawkdraw_shading_colors_clist % Store original bounding box values for later positioning of pattern \dim_set_eq:NN \l__hawkdraw_shading_bb_xmin_o_dim \l__hawkdraw_shading_bb_xmin_dim \dim_set_eq:NN \l__hawkdraw_shading_bb_xmax_o_dim \l__hawkdraw_shading_bb_xmax_dim \dim_set_eq:NN \l__hawkdraw_shading_bb_ymin_o_dim \l__hawkdraw_shading_bb_ymin_dim \dim_set_eq:NN \l__hawkdraw_shading_bb_ymax_o_dim \l__hawkdraw_shading_bb_ymax_dim \clist_if_in:NnT \l_hawkdraw_shading_path_use_clist { stroke } { \dim_set_eq:NN \l__hawkdraw_shading_path_linewidth_dim \l_hawkdraw_path_linewidth_dim } \bool_lazy_and:nnT { \l_hawkdraw_shading_circular_bool } { \str_if_eq_p:nn {#1} { radial } } { \dim_set:Nn \l__hawkdraw_shading_bb_xmax_dim { \dim_max:nn { \l__hawkdraw_shading_bb_xmax_dim } { \l__hawkdraw_shading_bb_ymax_dim } } \dim_set:Nn \l__hawkdraw_shading_bb_xmin_dim { \dim_min:nn { \l__hawkdraw_shading_bb_xmin_dim } { \l__hawkdraw_shading_bb_ymin_dim } } \dim_set_eq:NN \l__hawkdraw_shading_bb_ymax_dim \l__hawkdraw_shading_bb_xmax_dim \dim_set_eq:NN \l__hawkdraw_shading_bb_ymin_dim \l__hawkdraw_shading_bb_xmin_dim } \int_gincr:N \g__hawkdraw_shading_obj_int \pdf_object_unnamed_write:ne { dict } { /Type ~ /Pattern ~ /PatternType ~ 2 ~ /Shading ~ \tl_use:c { c__hawkdraw_shading_ #1 . \clist_use:N \l_hawkdraw_shading_colors_clist \str_if_eq:nnT {#1} { radial } { . \fp_to_decimal:n { \l_hawkdraw_shading_offset_fp } } \str_if_eq:nnT {#1} { conic } { . \fp_to_decimal:n { \l_hawkdraw_shading_angle_delta_fp } } _tl } ~ /Matrix ~ [ ~ \hawkdraw_pdf_transformation_matrix:nnnnnnn { -50bp } { -50bp } { ( \l__hawkdraw_shading_bb_xmax_dim - \l__hawkdraw_shading_bb_xmin_dim ) / 50bp } { ( \l__hawkdraw_shading_bb_ymax_dim - \l__hawkdraw_shading_bb_ymin_dim ) / 50bp } { \l_hawkdraw_shading_rotate_fp } { ( \l__hawkdraw_shading_bb_xmax_o_dim + \l__hawkdraw_shading_bb_xmin_o_dim ) / 2 + 0.5 * \l__hawkdraw_shading_path_linewidth_dim } { ( \l__hawkdraw_shading_bb_ymax_o_dim + \l__hawkdraw_shading_bb_ymin_o_dim ) / 2 + 0.5 * \l__hawkdraw_shading_path_linewidth_dim \fp_compare:nNnT { \l_hawkdraw_picture_baseline_fp } < { 0pt } { - \l_hawkdraw_picture_baseline_fp } } ~ ] ~ } \pdfmanagement_add:nee { Page / Resources / Pattern } { hawkdraw Shading \int_use:N \g__hawkdraw_shading_obj_int } { \pdf_object_ref_last: } \clist_if_in:NnT \l_hawkdraw_shading_path_use_clist { fill } { \hawkdraw_support_pdfliteral_direct:n { /Pattern ~ cs ~ /hawkdraw Shading \int_use:N \g__hawkdraw_shading_obj_int \c_space_tl scn ~ } } \clist_if_in:NnT \l_hawkdraw_shading_path_use_clist { stroke } { \hawkdraw_support_pdfliteral_direct:n { /Pattern ~ CS ~ /hawkdraw Shading \int_use:N \g__hawkdraw_shading_obj_int \c_space_tl SCN ~ } } } % === \cs_new_protected:Npn \__hawkdraw_shading_color_set_value:Nnnn #1#2#3#4 { \hawkdraw_case_color_space:nnn { \tl_set:Ne \l__hawkdraw_shading_color_value_tmp_tl {#2} \seq_put_right:NV #1 \l__hawkdraw_shading_color_value_tmp_tl } { \color_export:enN {#3} { space-sep-rgb } \l__hawkdraw_shading_color_value_tmp_tl \seq_put_right:NV #1 \l__hawkdraw_shading_color_value_tmp_tl } { \color_export:enN {#4} { space-sep-cmyk } \l__hawkdraw_shading_color_value_tmp_tl \seq_put_right:NV #1 \l__hawkdraw_shading_color_value_tmp_tl } } \cs_new_protected:Npn \hawkdraw_shading_color_set_values:Nn #1#2 { \seq_clear:N #1 \clist_map_inline:nn {#2} { \__hawkdraw_shading_color_set_value:Nnnn #1 {##1} {##1} {##1} } } \cs_generate_variant:Nn \hawkdraw_shading_color_set_values:Nn { NV } % === \cs_new_protected:Npn \hawkdraw_shading_create:nn #1#2 { \cs_if_exist_use:cTF { hawkdraw_shading_ #1 :n } { {#2} } { \msg_warning:nnn { hawkdraw } { shading-unknown } {#1} } } \cs_generate_variant:Nn \hawkdraw_shading_create:nn { nV } % === \cs_set:Npn \__hawkdraw_shading_linear_bounds:n #1 { \fp_format:nn { 25 } { .5 } ~ \int_step_tokens:nnn { 2 } { \clist_count:n {#1} - 1 } { \__hawkdraw_shading_linear_bounds_aux:nn { \clist_count:n {#1} } } \fp_format:nn { 75 } { .5 } ~ } \cs_set:Npn \__hawkdraw_shading_linear_bounds_aux:nn #1#2 { \fp_format:nn { ( 50 / ( #1 - 1 ) ) * ( #2 - 1 ) + 25 } { .5 } ~ } \cs_new:Npn \__hawkdraw_shading_linear_functions:n #1 { << ~ /FunctionType ~ 2 ~ /Domain ~ [ 0.0 ~ 100.0 ] ~ /C0 ~ [ \seq_item:Nn \l__hawkdraw_shading_color_values_seq { 1 } ] ~ /C1 ~ [ \seq_item:Nn \l__hawkdraw_shading_color_values_seq { 1 } ] ~ /N ~ 1 ~ >> ~ \int_step_function:nnN { 2 } { \seq_count:N \l__hawkdraw_shading_color_values_seq } \__hawkdraw_shading_linear_functions_aux:n << ~ /FunctionType ~ 2 ~ /Domain ~ [ 0.0 ~ 100.0 ] ~ /C0 ~ [ \seq_item:Nn \l__hawkdraw_shading_color_values_seq { -1 } ] ~ /C1 ~ [ \seq_item:Nn \l__hawkdraw_shading_color_values_seq { -1 } ] ~ /N ~ 1 ~ >> ~ } \cs_generate_variant:Nn \__hawkdraw_shading_linear_functions:n { V } \cs_new:Npn \__hawkdraw_shading_linear_functions_aux:n #1 { << ~ /FunctionType ~ 2 ~ /Domain ~ [ 0.0 ~ 100.0 ] ~ /C0 ~ [ \seq_item:Nn \l__hawkdraw_shading_color_values_seq { #1 - 1 } ] ~ /C1 ~ [ \seq_item:Nn \l__hawkdraw_shading_color_values_seq {#1} ] ~ /N ~ 1 ~ >> ~ } \cs_new_protected:Npn \hawkdraw_shading_linear:n #1 { \tl_if_exist:cF { c__hawkdraw_shading_ linear . #1 _tl } { \hawkdraw_shading_color_set_values:Nn \l__hawkdraw_shading_color_values_seq {#1} \hawkdraw_shading_set:nnn { linear . #1 } { /ShadingType ~ 2 ~ \hawkdraw_case_color_space:nnn { /ColorSpace ~ /DeviceGray ~ } { /ColorSpace ~ /DeviceRGB ~ } { /ColorSpace ~ /DeviceCMYK ~ } /Domain ~ [ 0.0 ~ 100.0 ] ~ /Coords ~ [ 0.0 ~ 0.0 ~ 0.0 ~ 100.0 ] ~ /Extend ~ [ false ~ false ] ~ /Function ~ << ~ /FunctionType ~ 3 ~ /Domain ~ [ 0.0 ~ 100.0 ] ~ /Functions ~ [ ~ \__hawkdraw_shading_linear_functions:V \l__hawkdraw_shading_color_values_seq ] ~ /Bounds ~ [ \__hawkdraw_shading_linear_bounds:n {#1} ] ~ /Encode ~ [ \prg_replicate:nn { \clist_count:n {#1} + 1 } { 0 ~ 1 ~ } ] ~ >> ~ } { } } } % === \cs_new:Npn \__hawkdraw_shading_radial_bounds:n #1 { \int_step_tokens:nn { \clist_count:n {#1} - 1 } { \__hawkdraw_shading_radial_bounds_aux:nn { \clist_count:n {#1} - 1 } } } \cs_new:Npn \__hawkdraw_shading_radial_bounds_aux:nn #1#2 { \fp_format:nn { ( 25 / ( #1 ) ) * ( #2 ) } { .3 } ~ } \cs_new:Npn \__hawkdraw_shading_radial_functions:n #1 { \int_step_function:nN { \seq_count:N \l__hawkdraw_shading_color_values_seq - 1 } \__hawkdraw_shading_radial_functions_aux:n << ~ /FunctionType ~ 2 ~ /Domain ~ [ 0.0 ~ 50.0 ] ~ /C0 ~ [ \seq_item:Nn \l__hawkdraw_shading_color_values_seq { -1 } ] ~ /C1 ~ [ \seq_item:Nn \l__hawkdraw_shading_color_values_seq { -1 } ] ~ /N ~ 1 ~ >> ~ } \cs_generate_variant:Nn \__hawkdraw_shading_radial_functions:n { V } \cs_new:Npn \__hawkdraw_shading_radial_functions_aux:n #1 { << ~ /FunctionType ~ 2 ~ /Domain ~ [ 0.0 ~ 50.0 ] ~ /C0 ~ [ \seq_item:Nn \l__hawkdraw_shading_color_values_seq {#1} ] ~ /C1 ~ [ \seq_item:Nn \l__hawkdraw_shading_color_values_seq { #1 + 1 } ] ~ /N ~ 1 ~ >> ~ } \cs_new:Npn \hawkdraw_shading_radial_offset:n #1 { \fp_format:nn { 50 + ( #1 * 25 ) } { .5 } ~ } \cs_new_protected:Npn \hawkdraw_shading_radial:n #1 { \tl_if_exist:cF { c__hawkdraw_shading_ radial . #1 . \fp_to_decimal:n { \l_hawkdraw_shading_offset_fp } _tl } { \hawkdraw_shading_color_set_values:Nn \l__hawkdraw_shading_color_values_seq {#1} \hawkdraw_shading_set:enn { radial . #1 . \fp_to_decimal:n { \l_hawkdraw_shading_offset_fp } } { /ShadingType ~ 3 ~ \hawkdraw_case_color_space:nnn { /ColorSpace ~ /DeviceGray ~ } { /ColorSpace ~ /DeviceRGB ~ } { /ColorSpace ~ /DeviceCMYK ~ } /Domain ~ [ 0.0 ~ 50.0 ] ~ /Coords ~ [ \hawkdraw_shading_radial_offset:n { \l_hawkdraw_shading_offset_fp } 50.0 ~ 0.0 ~ 50.0 ~ 50.0 ~ 50.0 ] ~ /Extend ~ [ true ~ false ] ~ /Function ~ << ~ /FunctionType ~ 3 ~ /Domain ~ [ 0.0 ~ 50.0 ] ~ /Functions ~ [ ~ \__hawkdraw_shading_radial_functions:V \l__hawkdraw_shading_color_values_seq ] ~ /Bounds ~ [ \__hawkdraw_shading_radial_bounds:n {#1} ] ~ /Encode ~ [ \prg_replicate:nn { \clist_count:n {#1} } { 0 ~ 1 ~ } ] ~ >> ~ } { } } } % === % We use a Coons patch mesh for conic shadings where multiple circular-segment shaped patches form a circle. % Two corners of the patch are at the center of the circle, the other two at the outer border forming a curve. % We use four patches for each color in order to be able to generate a circle (or at least an approximation) % with only two colors. Therefore, we need to interpolate a few colors so we end up with 2n + 1 colors. % In theory we can use patches with different flags and reduce the size of the stream, but in practice this % means that the path direction of every second patch needs to be reversed. Since we don't need a lot of % patches to create a conic shading, we just use flag-0 patches only. % We need to output a binary stream. It is theoretically possinle to output a hex stream and set the relevant % /Filter, but when PDFTeX compresses the stream, it simply appends a /Filter entry to the attributes of the % PDF object without taking into account an already existing /Filter entry which results in faulty syntax. % We need different approaches to output such a stream for PDFTeX and LuaTeX. Since dvipdfmx requires a hex % stream which it converts to a binary stream, we first create a hex stream. \cs_new_protected:Npn \hawkdraw_shading_conic_stream:N #1 { \tl_set:Ne #1 { \seq_map_indexed_function:NN \l__hawkdraw_shading_color_values_seq \__hawkdraw_shading_conic_stream_aux:nn } } \cs_new:Npn \__hawkdraw_shading_conic_stream_aux:nn #1#2 { % skip first entry in seq which is the start color \int_compare:nNnF {#1} = { \c_one_int } { % flag (4 bits) \hawkdraw_hex_to_stream:n { 00 } % patch is pie segment going from 0 deg to 360 / ( n * 4 ) deg % points (12 points, 2 * 16 bits each) \prg_replicate:nn { 2 } { \__hawkdraw_shading_conic_stream_point_polar:nn { 0 } { \l_hawkdraw_shading_angle_delta_fp / ( \seq_count:N \l__hawkdraw_shading_color_values_seq - 1 ) * ( #1 - 2 ) } } \prg_replicate:nn { 2 } { \__hawkdraw_shading_conic_stream_point_polar:nn { 1 } { \l_hawkdraw_shading_angle_delta_fp / ( \seq_count:N \l__hawkdraw_shading_color_values_seq - 1 ) * ( #1 - 2 ) } } \__hawkdraw_shading_conic_stream_point_polar:nn { 1 } { \l_hawkdraw_shading_angle_delta_fp / ( \seq_count:N \l__hawkdraw_shading_color_values_seq - 1 ) * ( #1 - 1.75 ) } \__hawkdraw_shading_conic_stream_point_polar:nn { 1 } { \l_hawkdraw_shading_angle_delta_fp / ( \seq_count:N \l__hawkdraw_shading_color_values_seq - 1 ) * ( #1 - 1.25 ) } \prg_replicate:nn { 2 } { \__hawkdraw_shading_conic_stream_point_polar:nn { 1 } { \l_hawkdraw_shading_angle_delta_fp / ( \seq_count:N \l__hawkdraw_shading_color_values_seq - 1 ) * ( #1 - 1 ) } } \prg_replicate:nn { 3 } { \__hawkdraw_shading_conic_stream_point_polar:nn { 0 } { \l_hawkdraw_shading_angle_delta_fp / ( \seq_count:N \l__hawkdraw_shading_color_values_seq - 1 ) * ( #1 - 1 ) } } \__hawkdraw_shading_conic_stream_point_polar:nn { 0 } { \l_hawkdraw_shading_angle_delta_fp / ( \seq_count:N \l__hawkdraw_shading_color_values_seq - 1 ) * ( #1 - 2 ) } % colors (4 colors, 3 * 8 bits each for RGB) \hawkdraw_hex_to_stream:e { \hawkdraw_color_pdf_to_hex:e { \seq_item:Nn \l__hawkdraw_shading_color_values_seq { #1 - 1 } } } \hawkdraw_hex_to_stream:e { \hawkdraw_color_pdf_to_hex:e { \seq_item:Nn \l__hawkdraw_shading_color_values_seq { #1 - 1 } } } \hawkdraw_hex_to_stream:e { \hawkdraw_color_pdf_to_hex:n {#2} } \hawkdraw_hex_to_stream:e { \hawkdraw_color_pdf_to_hex:n {#2} } } } \cs_new:Npn \__hawkdraw_shading_conic_stream_point_polar:nn #1#2 { % get coordinates from shifted point polar and normalize to FFFF \hawkdraw_hex_to_stream:e { \int_format:nn { \fp_to_int:n { \hawkdraw_tuple_use_i:n { ( 50bp , 50bp ) + ( \draw_point_polar:nn { ( #1 ) * 50bp } {#2} ) } / 100bp * 65535 } } { 0>4X } } \hawkdraw_hex_to_stream:e { \int_format:nn { \fp_to_int:n { \hawkdraw_tuple_use_ii:n { ( 50bp , 50bp ) + ( \draw_point_polar:nn { ( #1 ) * 50bp } {#2} ) } / 100bp * 65535 } } { 0>4X } } } \seq_new:N \l__hawkdraw_shading_color_values_tmp_seq \cs_new_protected:Npn \hawkdraw_shading_conic_color_set_values:Nn #1#2 { \seq_clear:N #1 \seq_set_from_clist:Nn \l__hawkdraw_shading_color_values_tmp_seq {#2} \seq_map_indexed_inline:Nn \l__hawkdraw_shading_color_values_tmp_seq { \int_compare:nNnTF {##1} = { \c_one_int } { % first entry is the start color \__hawkdraw_shading_color_set_value:Nnnn #1 {##2} {##2} {##2} } { \__hawkdraw_shading_color_set_value:Nnnn #1 { \fp_to_decimal:n { 0.75 * \seq_item:Nn \l__hawkdraw_shading_color_values_tmp_seq { ##1 - 1 } + 0.25 * ##2 } } { \seq_item:Nn \l__hawkdraw_shading_color_values_tmp_seq { ##1 - 1 } ! 75 ! ##2 } { \seq_item:Nn \l__hawkdraw_shading_color_values_tmp_seq { ##1 - 1 } ! 75 ! ##2 } \__hawkdraw_shading_color_set_value:Nnnn #1 { \fp_to_decimal:n { 0.5 * \seq_item:Nn \l__hawkdraw_shading_color_values_tmp_seq { ##1 - 1 } + 0.5 * ##2 } } { \seq_item:Nn \l__hawkdraw_shading_color_values_tmp_seq { ##1 - 1 } ! 50 ! ##2 } { \seq_item:Nn \l__hawkdraw_shading_color_values_tmp_seq { ##1 - 1 } ! 50 ! ##2 } \__hawkdraw_shading_color_set_value:Nnnn #1 { \fp_to_decimal:n { 0.25 * \seq_item:Nn \l__hawkdraw_shading_color_values_tmp_seq { ##1 - 1 } + 0.75 * ##2 } } { \seq_item:Nn \l__hawkdraw_shading_color_values_tmp_seq { ##1 - 1 } ! 25 ! ##2 } { \seq_item:Nn \l__hawkdraw_shading_color_values_tmp_seq { ##1 - 1 } ! 25 ! ##2 } \__hawkdraw_shading_color_set_value:Nnnn #1 {##2} {##2} {##2} } } } \tl_new:N \l__hawkdraw_shading_conic_stream_tl \cs_new_protected:Npn \hawkdraw_shading_conic:n #1 { \tl_if_exist:cF { c__hawkdraw_shading_ conic . #1 . \fp_to_decimal:n { \l_hawkdraw_shading_angle_delta_fp } _tl } { \hawkdraw_shading_conic_color_set_values:Nn \l__hawkdraw_shading_color_values_seq {#1} \hawkdraw_shading_conic_stream:N \l__hawkdraw_shading_conic_stream_tl \hawkdraw_shading_set:enn { conic . #1 . \fp_to_decimal:n { \l_hawkdraw_shading_angle_delta_fp } } { /ShadingType ~ 6 ~ \hawkdraw_case_color_space:nnn { /ColorSpace ~ /DeviceGray ~ } { /ColorSpace ~ /DeviceRGB ~ } { /ColorSpace ~ /DeviceCMYK ~ } /BitsPerCoordinate ~ 16 ~ /BitsPerComponent ~ 8 ~ /BitsPerFlag ~ 8 ~ /Decode ~ [ ~ 0 ~ 100 ~ 0 ~ 100 ~ \hawkdraw_case_color_space:nnn { 0 ~ 1 ~ } { 0 ~ 1 ~ 0 ~ 1 ~ 0 ~ 1 ~ } { 0 ~ 1 ~ 0 ~ 1 ~ 0 ~ 1 ~ 0 ~ 1 ~ } ] ~ } { \tl_use:N \l__hawkdraw_shading_conic_stream_tl } } } %EOF