Add fpng (#812)

* Create xmake.lua

* Update xmake.lua

* Update xmake.lua

* Update xmake.lua

* Update xmake.lua

* Update xmake.lua

* Update xmake.lua

packages/f/fpng/xmake.lua

@@ -0,0 +1,42 @@
+package("fpng")
+    set_homepage("https://github.com/richgel999/fpng")
+    set_description("Super fast C++ .PNG writer/reader")
+
+    add_urls("https://github.com/richgel999/fpng.git")
+    add_versions("2021.12.31", "4dae96d7876d17654ac5912449689f9f74ed9aae")
+
+    add_configs("sse4", { description = "Enable SSE 4.1 support.", default = false, type = "boolean"})
+
+    on_install("windows", "linux", "macosx", function (package)
+        io.writefile("xmake.lua", [[
+            add_rules("mode.debug", "mode.release")
+            option("sse4", {showmenu = true, default = false})
+            target("fpng")
+                set_kind("$(kind)")
+                add_files("src/fpng.cpp")
+                add_headerfiles("src/fpng.h")
+                if has_config("sse4") then
+                    add_defines("FPNG_NO_SSE=0")
+                    add_cxflags("-msse4.1", "-mpclmul")
+                else
+                    add_defines("FPNG_NO_SSE=1")
+                end
+                if is_plat("windows") and is_kind("shared") then
+                    add_rules("utils.symbols.export_all", {export_classes = true})
+                end
+        ]])
+        local configs = {sse4 = package:config("sse4")}
+        if package:config("shared") then
+            configs.kind = "shared"
+        end
+        import("package.tools.xmake").install(package, configs)
+    end)
+
+    on_test(function (package)
+        assert(package:check_cxxsnippets({test = [[
+            void test() {
+                std::vector<uint8_t> fpng_file_buf;
+	 	fpng::fpng_encode_image_to_memory(0, 0, 0, 0, fpng_file_buf, 0);
+            }
+        ]]}, {configs = {languages = "c++11"}, includes = "fpng.h"}))
+    end)