CMAKE: Add target for asy-latex.pdf.

cmake-scripts/docgen.cmake

@@ -1,3 +1,26 @@
 if (NOT ENABLE_DOCGEN_DEFAULT)
     message(FATAL_ERROR "Documentation generation is disabled")
 endif()
+
+set(ASY_DOC_ROOT ${CMAKE_CURRENT_SOURCE_DIR}/doc)
+set(ASY_TEX_BUILD_ROOT ${CMAKE_CURRENT_BINARY_DIR}/docbuild)
+file(MAKE_DIRECTORY ${ASY_TEX_BUILD_ROOT})
+configure_file(${ASY_RESOURCE_DIR}/version.texi.in ${ASY_TEX_BUILD_ROOT}/version.texi)
+
+find_package(LATEX COMPONENTS PDFLATEX REQUIRED)
+list(
+        TRANSFORM LATEX_ARTIFRACT_EXTENSIONS
+        PREPEND ${ASY_TEX_BUILD_ROOT}/asy-latex.
+        OUTPUT_VARIABLE ASY_LATEX_DTX_ARTIFACTS
+)
+
+add_custom_command(
+        OUTPUT ${ASY_TEX_BUILD_ROOT}/asy-latex.pdf ${ASY_TEX_BUILD_ROOT}/asymptote.sty
+        DEPENDS ${ASY_DOC_ROOT}/asy-latex.dtx
+        COMMAND ${PDFLATEX_COMPILER}
+        -include-directory=${ASY_TEX_BUILD_ROOT}
+        -output-directory=${ASY_TEX_BUILD_ROOT}
+        ${ASY_DOC_ROOT}/asy-latex.dtx
+        WORKING_DIRECTORY ${ASY_DOC_ROOT}
+        BYPRODUCTS ${ASY_LATEX_DTX_ARTIFACTS}
+)