Coin: Remove from qt4 portgroup and add a patch

* Coin itself doesn't need qt4, though SoQt / Quarter does.
* Added a patch to add a missing static_cast for building on newer
  Clang versions.

graphics/Coin/Portfile

@@ -1,12 +1,11 @@
 # -*- coding: utf-8; mode: tcl; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- vim:fenc=utf-8:ft=tcl:et:sw=4:ts=4:sts=4
 
 PortSystem          1.0
-PortGroup           qt4 1.0
 PortGroup           bitbucket 1.0
 
 bitbucket.setup     Coin3D coin 3.1.3 Coin-
 name                Coin
-revision            7
+revision            8
 license             BSD
 description         cross platform C++ OpenGL scene graph library
 long_description    Coin is a high-level 3D graphics library with a   \
@@ -38,7 +37,8 @@ patchfiles          configure.patch \
                     clang-name-lookup.diff \
                     fix-weird-error.diff \
                     patch-include-Inventor-C-base-math-undefs.h.diff \
-                    patch-Info.plist.in.diff
+                    patch-Info.plist.in.diff \
+                    add-static-cast.diff
 
 configure.args-append \
                     --disable-debug \

graphics/Coin/files/add-static-cast.diff

@@ -0,0 +1,11 @@
+--- src/misc/SoOffscreenRenderer.cpp	2010-03-02 08:20:09
++++ src/misc/SoOffscreenRenderer.cpp	2026-05-02 04:59:06
+@@ -1655,7 +1655,7 @@
+   if (renderaction->getNumPasses() > 1) {
+     SbVec3f jittervec;
+     SbMatrix m;
+-    const int vpsize[2] = { this->glcanvassize[0], this->glcanvassize[1] };
++    const int vpsize[2] = { static_cast<int>(this->glcanvassize[0]), static_cast<int>(this->glcanvassize[1]) };
+     coin_viewvolume_jitter(renderaction->getNumPasses(), renderaction->getCurPass(),
+                            vpsize, (float *)jittervec.getValue());
+     m.setTranslate(jittervec);