gnu: Add vtk-7.

* gnu/packages/image-processing.scm: (vtk-7): New variable.
* gnu/packages/patches/vtk-7-gcc-10-compat.patch: New patch.
* gnu/packages/patches/vtk-7-hdf5-compat.patch: Likewise.
* gnu/packages/patches/vtk-7-python-compat.patch: Likewise.
* gnu/local.mk (dist_patch_DATA): Register them.

gnu/local.mk

@@ -1935,6 +1935,9 @@ dist_patch_DATA =						\
   %D%/packages/patches/vte-CVE-2012-2738-pt1.patch			\
   %D%/packages/patches/vte-CVE-2012-2738-pt2.patch			\
   %D%/packages/patches/vtk-fix-freetypetools-build-failure.patch	\
+  %D%/packages/patches/vtk-7-gcc-10-compat.patch		\
+  %D%/packages/patches/vtk-7-hdf5-compat.patch			\
+  %D%/packages/patches/vtk-7-python-compat.patch		\
   %D%/packages/patches/warsow-qfusion-fix-bool-return-type.patch	\
   %D%/packages/patches/webkitgtk-adjust-bubblewrap-paths.patch	\
   %D%/packages/patches/webrtc-audio-processing-big-endian.patch	\

gnu/packages/image-processing.scm

@@ -407,6 +407,28 @@ a suite of 3D interaction widgets, supports parallel processing, and
 integrates with various databases on GUI toolkits such as Qt and Tk.")
     (license license:bsd-3)))
 
+(define-public vtk-7
+  (package
+    (inherit vtk)
+    (version "7.1.1")
+    (source (origin
+              (method url-fetch)
+              (uri (string-append "https://vtk.org/files/release/"
+                                  (version-major+minor version)
+                                  "/VTK-" version ".tar.gz"))
+              (sha256
+               (base32
+                "0nm7xwwj7rnsxjdv2ssviys8nhci4n9iiiqm2y14s520hl2dsp1d"))
+              (patches (search-patches "vtk-7-python-compat.patch"
+                                       "vtk-7-hdf5-compat.patch"
+                                       "vtk-7-gcc-10-compat.patch"))))
+    (arguments
+     (substitute-keyword-arguments (package-arguments vtk)
+       ((#:configure-flags flags)
+        ;; Otherwise, the build would fail with: "error: invalid conversion
+        ;; from ‘const char*’ to ‘char*’ [-fpermissive]".
+        `(cons "-DCMAKE_CXX_FLAGS=-fpermissive" ,flags))))))
+
 ;; itksnap needs an older variant of VTK.
 (define-public vtk-6
   (package (inherit vtk)

gnu/packages/patches/vtk-7-gcc-10-compat.patch

@@ -0,0 +1,14 @@
+Retrieved from
+https://sources.debian.org/src/vtk7/7.1.1%2Bdfsg2-10.1/debian/patches/.
+
+--- a/CMake/VTKGenerateExportHeader.cmake
++++ b/CMake/VTKGenerateExportHeader.cmake
+@@ -174,7 +174,7 @@
+     execute_process(COMMAND ${CMAKE_C_COMPILER} --version
+       OUTPUT_VARIABLE _gcc_version_info
+       ERROR_VARIABLE _gcc_version_info)
+-    string(REGEX MATCH "[3-9]\\.[0-9]\\.[0-9]*"
++    string(REGEX MATCH "[0-9]*\\.[0-9]\\.[0-9]*"
+       _gcc_version "${_gcc_version_info}")
+     # gcc on mac just reports: "gcc (GCC) 3.3 20030304 ..." without the
+     # patch level, handle this here:

gnu/packages/patches/vtk-7-hdf5-compat.patch

@@ -0,0 +1,38 @@
+Description: The H5FD_class_t struct gained an extra member in 1.10
+Bug-Debian: https://bugs.debian.org/846372
+Author: Iain Lane <iain.lane@canonical.com>
+--- a/ThirdParty/xdmf2/vtkxdmf2/libsrc/XdmfH5Driver.cxx
++++ b/ThirdParty/xdmf2/vtkxdmf2/libsrc/XdmfH5Driver.cxx
+@@ -139,7 +139,11 @@
+ #if (H5_VERS_MAJOR>1)||((H5_VERS_MAJOR==1)&&(H5_VERS_MINOR>=8))
+ static haddr_t H5FD_dsm_get_eoa(const H5FD_t *_file, H5FD_mem_t type);
+ static herr_t H5FD_dsm_set_eoa(H5FD_t *_file, H5FD_mem_t type, haddr_t addr);
++#if (H5_VERS_MAJOR>1)||((H5_VERS_MAJOR==1)&&(H5_VERS_MINOR>=10))
++static haddr_t H5FD_dsm_get_eof(const H5FD_t *_file, H5FD_mem_t type);
++#else
+ static haddr_t H5FD_dsm_get_eof(const H5FD_t *_file);
++#endif
+ #else
+ static haddr_t H5FD_dsm_get_eoa(H5FD_t *_file);
+ static herr_t H5FD_dsm_set_eoa(H5FD_t *_file, haddr_t addr);
+@@ -155,6 +159,9 @@
+     "dsm",                      /*name          */
+     MAXADDR,                    /*maxaddr       */
+     H5F_CLOSE_WEAK,             /*fc_degree     */
++#if (H5_VERS_MAJOR>1)||((H5_VERS_MAJOR==1)&&(H5_VERS_MINOR>=8))
++    NULL,                       /* terminate    */
++#endif
+     NULL,                       /*sb_size       */
+     NULL,                       /*sb_encode     */
+     NULL,                       /*sb_decode     */
+@@ -687,7 +694,9 @@
+  *-------------------------------------------------------------------------
+  */
+ static haddr_t
+-#if (H5_VERS_MAJOR>1)||((H5_VERS_MAJOR==1)&&(H5_VERS_MINOR>=8))
++#if (H5_VERS_MAJOR>1)||((H5_VERS_MAJOR==1)&&(H5_VERS_MINOR>=10))
++H5FD_dsm_get_eof(const H5FD_t *_file, H5FD_mem_t type)
++#elif (H5_VERS_MAJOR>1)||((H5_VERS_MAJOR==1)&&(H5_VERS_MINOR>=8))
+ H5FD_dsm_get_eof(const H5FD_t *_file)
+ #else
+ H5FD_dsm_get_eof(H5FD_t *_file)

gnu/packages/patches/vtk-7-python-compat.patch

@@ -0,0 +1,16 @@
+Author: Gert Wollny <gewo@debian.org>
+Description: Work around compile bug with python 3.7.1
+Debian-Bug: https://bugs.debian.org/914347
+diff --git a/Wrapping/PythonCore/vtkPythonArgs.cxx b/Wrapping/PythonCore/vtkPythonArgs.cxx
+index 1b1e4b9..682f8b8 100644
+--- a/Wrapping/PythonCore/vtkPythonArgs.cxx
++++ b/Wrapping/PythonCore/vtkPythonArgs.cxx
+@@ -102,7 +102,7 @@ bool vtkPythonGetStringValue(PyObject *o, T *&a, const char *exctext)
+   else if (PyUnicode_Check(o))
+   {
+ #if PY_VERSION_HEX >= 0x03030000
+-    a = PyUnicode_AsUTF8(o);
++    a = const_cast<char*>(PyUnicode_AsUTF8(o));
+     return true;
+ #else
+     PyObject *s = _PyUnicode_AsDefaultEncodedString(o, NULL);