\ProvidesFile{pgf-go-images.sty}[2026/10/23 v0.2026.10.23 pgf-go: images]
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%IMAGENES (PNG, JPG O PDF) DE LAS PIEDRAS, EL FONDO, LA CUADRICULA, LOS HOSHI Y LAS MARCAS.
%CON pdfTeX Y LuaTeX (SALIDA PDF) CADA ARCHIVO, CON CADA TAMANO, SE GUARDA UNA SOLA VEZ EN UN Form
%XObject QUE SE REUSA EN TODOS LOS DIBUJOS. LA SOMBRA DE UNA IMAGEN USA ESE MISMO Form COMO MASCARA
%(CANAL ALFA): TIENE LA FORMA DE LA IMAGEN. CON OTROS MOTORES LA IMAGEN SE INCLUYE CADA VEZ Y LA
%SOMBRA NO SE DIBUJA.

%"ARCHIVO|OPCIONES" -> {Form}{ANCHO}{ALTO}{ARCHIVO}{OPCIONES}. Form VACIO SI NO HAY Form XObject.
\prop_new:N \g__pgfgo_image_prop
%LOS Form CUYA MASCARA YA ESTA EN LOS RECURSOS (ExtGState).
\prop_new:N \g__pgfgo_image_mask_prop
\box_new:N \l__pgfgo_image_box
\tl_new:N \l__pgfgo_image_key_tl
\tl_new:N \l__pgfgo_image_tl
\tl_new:N \l__pgfgo_image_file_tl
\tl_new:N \l__pgfgo_image_options_tl

%LA ULTIMA IMAGEN CARGADA.
\tl_new:N \l_pgfgo_image_form_tl
\dim_new:N \l_pgfgo_image_width_dim
\dim_new:N \l_pgfgo_image_height_dim

\msg_new:nnn {pgfgo} {image-shadow}
	{The~shadow~or~the~silhouette~of~an~image~needs~pdfTeX~or~LuaTeX~with~PDF~output.~It~is~not~drawn.}
\bool_new:N \g__pgfgo_image_shadow_warned_bool

%SEGUN EL MOTOR: \__pgfgo_image_save: GUARDA \l__pgfgo_image_box EN UN Form (O DEJA VACIO
%\l_pgfgo_image_form_tl) Y \__pgfgo_image_put: PONE LA ULTIMA IMAGEN CARGADA.
\cs_new_protected:Npn \__pgfgo_image_define_none: {
	\cs_new_protected:Npn \__pgfgo_image_save: {\tl_clear:N \l_pgfgo_image_form_tl}
	\cs_new_protected:Npn \__pgfgo_image_put: {
		\use:e {
			\exp_not:N \includegraphics [\exp_not:V \l__pgfgo_image_options_tl]
				{\exp_not:V \l__pgfgo_image_file_tl}
		}
	}
}
\sys_if_output_pdf:TF
	{
		\sys_if_engine_luatex:TF
			{
				\cs_new_protected:Npn \__pgfgo_image_save: {
					\tex_immediate:D \saveboxresource
						attr {/Group~<<~/S~/Transparency~/CS~/DeviceRGB~>>} \l__pgfgo_image_box
					\tl_set:Ne \l_pgfgo_image_form_tl {\int_use:N \lastsavedboxresourceindex}
				}
				\cs_new_protected:Npn \__pgfgo_image_put: {\useboxresource \l_pgfgo_image_form_tl \scan_stop:}
			}
			{
				\sys_if_engine_pdftex:TF
					{
						\cs_new_protected:Npn \__pgfgo_image_save: {
							\tex_immediate:D \pdfxform
								attr {/Group~<<~/S~/Transparency~/CS~/DeviceRGB~>>} \l__pgfgo_image_box
							\tl_set:Ne \l_pgfgo_image_form_tl {\int_use:N \pdflastxform}
						}
						\cs_new_protected:Npn \__pgfgo_image_put: {\pdfrefxform \l_pgfgo_image_form_tl \scan_stop:}
					}
					{\__pgfgo_image_define_none:}
			}
	}
	{\__pgfgo_image_define_none:}

\cs_new_protected:Npn \__pgfgo_image_set:nnnnn #1#2#3#4#5 {
	\tl_set:Nn \l_pgfgo_image_form_tl {#1}
	\dim_set:Nn \l_pgfgo_image_width_dim {#2}
	\dim_set:Nn \l_pgfgo_image_height_dim {#3}
	\tl_set:Nn \l__pgfgo_image_file_tl {#4}
	\tl_set:Nn \l__pgfgo_image_options_tl {#5}
}

%EL TAMANO DE LA IMAGEN QUE QUEDO EN \l__pgfgo_image_box.
\cs_new_protected:Npn \__pgfgo_image_box_size: {
	\dim_set:Nn \l_pgfgo_image_width_dim {\box_wd:N \l__pgfgo_image_box}
	\dim_set:Nn \l_pgfgo_image_height_dim {\box_ht:N \l__pgfgo_image_box + \box_dp:N \l__pgfgo_image_box}
}

%LAS IMAGENES DE LOS PERFILES (pgfgo-board.jpg, ...) ESTAN EN LA CARPETA DE pgf-go.sty (POR EJ.
%\usepackage{../../latex/pgf-go}). UN ARCHIVO QUE NO SE ENCUENTRA (NI EN LA CARPETA DEL DOCUMENTO NI EN EL
%PATH DE TEX) SE BUSCA AHI; SI TAMPOCO ESTA, QUEDA COMO ESTA (\includegraphics LO BUSCA EN \graphicspath).
%INSTALADO, \c__pgfgo_path_tl ESTA VACIO Y LAS IMAGENES SE ENCUENTRAN EN EL PATH DE TEX. EN ESA CARPETA SE
%PRUEBA EL NOMBRE TAL CUAL Y CON LAS EXTENSIONES DE \c__pgfgo_image_extensions_clist (COMO HACE
%\includegraphics CON UN NOMBRE SIN EXTENSION).
\tl_const:Ne \c__pgfgo_image_dir_tl {\tl_if_empty:NF \c__pgfgo_path_tl {\c__pgfgo_path_tl /}}
\clist_const:Nn \c__pgfgo_image_extensions_clist {{}, .pdf, .png, .jpg, .jpeg}
\tl_new:N \l__pgfgo_image_path_tl
\cs_new_protected:Npn \__pgfgo_image_locate:n #1 {
	\tl_set:Nn \l__pgfgo_image_path_tl {#1}
	\tl_if_empty:NF \c__pgfgo_image_dir_tl {
		\file_if_exist:nF {#1} {
			\clist_map_inline:Nn \c__pgfgo_image_extensions_clist {
				\file_if_exist:nT {\c__pgfgo_image_dir_tl #1 ##1} {
					\tl_set:Ne \l__pgfgo_image_path_tl {\exp_not:V \c__pgfgo_image_dir_tl \exp_not:n {#1 ##1}}
					\clist_map_break:
				}
			}
		}
	}
}

%CARGA LA IMAGEN #1 CON LAS OPCIONES #2 DE \includegraphics (width, height). LA PRIMERA VEZ CREA EL Form.
\cs_new_protected:Npn \pgfgo_image_load:nn #1#2 {
	\tl_set:Ne \l__pgfgo_image_key_tl {\tl_to_str:n {#1} | \tl_to_str:n {#2}}
	\prop_get:NVNTF \g__pgfgo_image_prop \l__pgfgo_image_key_tl \l__pgfgo_image_tl
		{\exp_after:wN \__pgfgo_image_set:nnnnn \l__pgfgo_image_tl}
		{
			\__pgfgo_image_locate:n {#1}
			\hbox_set:Nn \l__pgfgo_image_box {\includegraphics [#2] {\l__pgfgo_image_path_tl}}
			\__pgfgo_image_box_size:
			\__pgfgo_image_save:
			\prop_gput:NVe \g__pgfgo_image_prop \l__pgfgo_image_key_tl {
				{\l_pgfgo_image_form_tl}
				{\dim_use:N \l_pgfgo_image_width_dim} {\dim_use:N \l_pgfgo_image_height_dim}
				{\exp_not:V \l__pgfgo_image_path_tl} {\exp_not:n {#2}}
			}
			\tl_set_eq:NN \l__pgfgo_image_file_tl \l__pgfgo_image_path_tl
			\tl_set:Nn \l__pgfgo_image_options_tl {#2}
		}
}
\cs_generate_variant:Nn \pgfgo_image_load:nn {ne, Ve, ee}
\cs_generate_variant:Nn \prop_gput:Nnn {NVe}
\cs_generate_variant:Nn \prop_get:NnNTF {NV}
\cs_generate_variant:Nn \str_case:nn {V}

%EL TAMANO NATURAL DE LA IMAGEN #1, SIN CREAR UN Form.
\prop_new:N \g__pgfgo_image_natural_prop
\cs_new_protected:Npn \pgfgo_image_measure:n #1 {
	\tl_set:Ne \l__pgfgo_image_key_tl {\tl_to_str:n {#1}}
	\prop_get:NVNTF \g__pgfgo_image_natural_prop \l__pgfgo_image_key_tl \l__pgfgo_image_tl
		{\exp_after:wN \__pgfgo_image_natural:nn \l__pgfgo_image_tl}
		{
			\__pgfgo_image_locate:n {#1}
			\hbox_set:Nn \l__pgfgo_image_box {\includegraphics [draft] {\l__pgfgo_image_path_tl}}
			\__pgfgo_image_box_size:
			\prop_gput:NVe \g__pgfgo_image_natural_prop \l__pgfgo_image_key_tl
				{{\dim_use:N \l_pgfgo_image_width_dim} {\dim_use:N \l_pgfgo_image_height_dim}}
		}
}
\cs_generate_variant:Nn \pgfgo_image_measure:n {V}
\cs_new_protected:Npn \__pgfgo_image_natural:nn #1#2 {
	\dim_set:Nn \l_pgfgo_image_width_dim {#1}
	\dim_set:Nn \l_pgfgo_image_height_dim {#2}
}

%CON VARIOS ARCHIVOS, CUAL (1 A #3) VA EN EL LUGAR (#1,#2): UN PSEUDOAZAR QUE SOLO DEPENDE DEL LUGAR
%(SIEMPRE EL MISMO, EN CUALQUIER MOTOR) Y QUE NO ES EL DE LOS GIROS: EL ARCHIVO Y EL GIRO NO VAN JUNTOS.
\cs_new:Npn \pgfgo_image_pick:nnn #1#2#3 {
	\fp_eval:n {
		floor((sin((#1) * 39.3468 + (#2) * 11.135) * 24634.6345
			- floor(sin((#1) * 39.3468 + (#2) * 11.135) * 24634.6345)) * (#3)) + 1
	}
}

%LA ULTIMA IMAGEN CARGADA, EN UNA CAJA.
\cs_new_protected:Npn \pgfgo_image_use: {\hbox:n {\__pgfgo_image_put:}}

%DIBUJA LA ULTIMA IMAGEN CARGADA, CENTRADA EN #1 (UN PUNTO DE PGF). \pgftext AGRANDA EL TAMANO DEL
%CAMINO ACTUAL (GLOBAL), Y EL PROXIMO \pgfusepath LO SUMA A LA CAJA DEL DIBUJO: UNA IMAGEN RECORTADA
%(LAS BALDOSAS DEL FONDO) LA AGRANDARIA. \pgfinterruptpath LO GUARDA Y LO DEVUELVE.
\cs_new_protected:Npn \pgfgo_image_draw:n #1 {
	\pgfinterruptpath
		\pgftext [at = {#1}] {\pgfgo_image_use:}
	\endpgfinterruptpath
}
\cs_new_protected:Npn \pgfgo_image_draw: {\pgfgo_image_draw:n {\pgfpointorigin}}

%LA SOMBRA DE LA ULTIMA IMAGEN CARGADA, CENTRADA EN EL ORIGEN: UN RECTANGULO DEL COLOR DE RELLENO
%ACTUAL, RECORTADO POR EL CANAL ALFA DE LA IMAGEN. EL DESPLAZAMIENTO Y LA OPACIDAD LOS PONE QUIEN LLAMA.
\cs_new_protected:Npn \pgfgo_image_shadow: {
	\tl_if_empty:NTF \l_pgfgo_image_form_tl
		{
			\bool_if:NF \g__pgfgo_image_shadow_warned_bool {
				\msg_warning:nn {pgfgo} {image-shadow}
				\bool_gset_true:N \g__pgfgo_image_shadow_warned_bool
			}
		}
		{
			\prop_if_in:NVF \g__pgfgo_image_mask_prop \l_pgfgo_image_form_tl {
				\cs_if_exist_use:c {pgf@sys@pdf@check@resources}
				\use:e {
					\exp_not:c {pgfutil@addpdfresource@extgs} {
						/pgfgoalpha \l_pgfgo_image_form_tl \c_space_tl
						<< /SMask \c_space_tl << /S \c_space_tl /Alpha \c_space_tl
							/G \c_space_tl \l_pgfgo_image_form_tl \c_space_tl 0 \c_space_tl R >> >>
					}
				}
				\prop_gput:NVn \g__pgfgo_image_mask_prop \l_pgfgo_image_form_tl {}
			}
			\pgfscope
				%LA MASCARA QUEDA CON SU ESQUINA INFERIOR IZQUIERDA EN EL ORIGEN DEL SISTEMA DE COORDENADAS
				%DEL MOMENTO EN QUE SE ACTIVA.
				\pgftransformshift {\pgfpoint {-0.5\l_pgfgo_image_width_dim} {-0.5\l_pgfgo_image_height_dim}}
				\pgflowlevelsynccm
				\use:e {\exp_not:c {pgfsysprotocol@literal} {/pgfgoalpha \l_pgfgo_image_form_tl \c_space_tl gs}}
				\pgfpathrectangle {\pgfpointorigin} {\pgfpoint {\l_pgfgo_image_width_dim} {\l_pgfgo_image_height_dim}}
				\pgfusepath {fill}
			\endpgfscope
		}
}
\cs_generate_variant:Nn \prop_if_in:NnF {NV}
\cs_generate_variant:Nn \prop_gput:Nnn {NVn}

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