[workspace] Use libpng from BCR

MODULE.bazel

@@ -92,6 +92,7 @@ bazel_dep(name = "glib", version = "2.82.2.bcr.10", repo_name = "module_glib")
 # implementation.
 
 bazel_dep(name = "libjpeg_turbo", version = "3.1.3.bcr.6", repo_name = "module_libjpeg")
+bazel_dep(name = "libpng", version = "1.6.58", repo_name = "module_libpng")
 bazel_dep(name = "nanobind", version = "3.0.0", repo_name = "module_nanobind")
 bazel_dep(name = "nlohmann_json", version = "3.12.0.bcr.2", repo_name = "module_nlohmann_json")
 bazel_dep(name = "robin-map", version = "1.4.1", repo_name = "module_robin_map")
@@ -190,6 +191,7 @@ use_repo(
     # but (unlike the prior group) these are not configurable.
     #
     "libjpeg",
+    "libpng",
     "nlohmann_json",
     "suitesparse",
     "zlib",
@@ -323,7 +325,6 @@ use_repo(
     "ipopt_internal",
     "lapack_internal",
     "lcm_internal",
-    "libpng_internal",
     "libtiff_internal",
     "libzip_internal",
     "metis_internal",

tools/workspace/BUILD.bazel

@@ -37,7 +37,6 @@ filegroup(
         "@ipopt_internal//:drake_repository_metadata.json",
         "@lapack_internal//:drake_repository_metadata.json",
         "@lcm_internal//:drake_repository_metadata.json",
-        "@libpng_internal//:drake_repository_metadata.json",
         "@libtiff_internal//:drake_repository_metadata.json",
         "@libzip_internal//:drake_repository_metadata.json",
         "@meshcat//:drake_repository_metadata.json",
@@ -185,7 +184,6 @@ _DRAKE_EXTERNAL_PACKAGE_INSTALLS = ["@%s//:install" % p for p in [
     "gz_math_internal",
     "gz_utils_internal",
     "ipopt_internal",
-    "libpng_internal",
     "libtiff_internal",
     "libzip_internal",
     "meshcat",
@@ -216,6 +214,7 @@ _DRAKE_EXTERNAL_PACKAGE_INSTALLS = ["@%s//:install" % p for p in [
     "highway_internal",
     "lapack",
     "libjpeg",
+    "libpng",
     # N.B. The nanobind install is handled by //bindings/pydrake:install.
     "nlohmann_json",
     "opencl",

tools/workspace/default.bzl

@@ -27,7 +27,6 @@ load("//tools/workspace/implib_so_internal:repository.bzl", "implib_so_internal_
 load("//tools/workspace/ipopt_internal:repository.bzl", "ipopt_internal_repository")  # noqa
 load("//tools/workspace/lapack_internal:repository.bzl", "lapack_internal_repository")  # noqa
 load("//tools/workspace/lcm_internal:repository.bzl", "lcm_internal_repository")
-load("//tools/workspace/libpng_internal:repository.bzl", "libpng_internal_repository")  # noqa
 load("//tools/workspace/libtiff_internal:repository.bzl", "libtiff_internal_repository")  # noqa
 load("//tools/workspace/libzip_internal:repository.bzl", "libzip_internal_repository")  # noqa
 load("//tools/workspace/meshcat:repository.bzl", "meshcat_repository")
@@ -102,7 +101,6 @@ def _add_internal_repositories():
     ipopt_internal_repository(name = "ipopt_internal", mirrors = mirrors)
     lapack_internal_repository(name = "lapack_internal", mirrors = mirrors)
     lcm_internal_repository(name = "lcm_internal", mirrors = mirrors)
-    libpng_internal_repository(name = "libpng_internal", mirrors = mirrors)
     libtiff_internal_repository(name = "libtiff_internal", mirrors = mirrors)
     libzip_internal_repository(name = "libzip_internal", mirrors = mirrors)
     metis_internal_repository(name = "metis_internal", mirrors = mirrors)
@@ -164,6 +162,7 @@ def _drake_dep_repositories_impl(module_ctx):
         },
         "lapack": "lapack",
         "libjpeg": "libjpeg",
+        "libpng": "libpng",
         "nlohmann_json": {
             # We provide both aliases, since Drake first-party only needs
             # :singleheader-json but third-party (VTK) needs :json.

tools/workspace/libpng/BUILD.bazel

@@ -0,0 +1,25 @@
+load("@drake//tools/skylark:cc_hidden.bzl", "cc_static_hidden_library")
+load("//tools/install:install.bzl", "install", "install_files")
+load("//tools/lint:lint.bzl", "add_lint_tests")
+
+package(default_visibility = ["//visibility:private"])
+
+cc_static_hidden_library(
+    name = "libpng",
+    visibility = ["//visibility:public"],
+    deps = ["@module_libpng//:libpng"],
+)
+
+install_files(
+    name = "install_license",
+    dest = "share/doc/libpng",
+    files = ["@module_libpng//:license"],
+)
+
+install(
+    name = "install",
+    visibility = ["//tools/workspace:__pkg__"],
+    deps = [":install_license"],
+)
+
+add_lint_tests()

tools/workspace/vtk_internal/settings.bzl

@@ -632,7 +632,7 @@ MODULE_SETTINGS = {
             "VTK_MODULE_USE_EXTERNAL_vtkpng=1",
         ],
         "deps_extra": [
-            "@libpng_internal//:libpng",
+            "@libpng//:libpng",
         ],
     },
     "VTK::tiff": {