add meshoptimizer (#1768)

* add meshoptimizer

* fix test for meshoptimizer

* fix test again

packages/m/meshoptimizer/xmake.lua

@@ -0,0 +1,41 @@
+package("meshoptimizer")
+
+    set_homepage("https://github.com/zeux/meshoptimizer")
+    set_description("Mesh optimization library that makes meshes smaller and faster to render")
+    set_license("MIT")
+
+    add_urls("https://github.com/zeux/meshoptimizer/archive/refs/tags/$(version).tar.gz",
+             "https://github.com/zeux/meshoptimizer.git")
+    add_versions("v0.18", "f5bc07d7322e6292fe0afce03462b5c394d111386236f926fdc44d2aff3b854b")
+
+    add_deps("cmake")
+    on_load("windows", function (package)
+        if package:config("shared") then
+            package:add("defines", "MESHOPTIMIZER_API=__declspec(dllimport)")
+        end
+    end)
+
+    on_install("windows", "macosx", "linux", function (package)
+        local configs = {}
+        table.insert(configs, "-DCMAKE_BUILD_TYPE=" .. (package:debug() and "Debug" or "Release"))
+        table.insert(configs, "-DMESHOPT_BUILD_SHARED_LIBS=" .. (package:config("shared") and "ON" or "OFF"))
+        import("package.tools.cmake").install(package, configs)
+    end)
+
+    on_test(function (package)
+        assert(package:check_cxxsnippets({test = [[
+            #include <vector>
+            struct Vertex
+            {
+                float px, py, pz;
+                float nx, ny, nz;
+                float tx, ty;
+            };
+            void test() {
+                size_t total_indices = 0;
+                std::vector<Vertex> vertices(total_indices);
+                std::vector<unsigned int> remap(total_indices);
+                size_t total_vertices = meshopt_generateVertexRemap(&remap[0], NULL, total_indices, &vertices[0], total_indices, sizeof(Vertex));
+            }
+        ]]}, {configs = {language = "cxx11"}, includes = "meshoptimizer.h"}))
+    end)