metal: initial work on windowing and instance creation

src/modules/graphics/Graphics.cpp

@@ -32,6 +32,7 @@
 #include "Video.h"
 #include "Text.h"
 #include "common/deprecation.h"
+#include "common/config.h"
 
 // C++
 #include <algorithm>
@@ -106,6 +107,36 @@ love::Type Graphics::type("graphics", &Module::type);
 
 Graphics::DefaultShaderCode Graphics::defaultShaderCode[Shader::STANDARD_MAX_ENUM][Shader::LANGUAGE_MAX_ENUM][2];
 
+namespace opengl { extern love::graphics::Graphics *createInstance(); }
+#if defined(LOVE_MACOS) || defined(LOVE_IOS)
+namespace metal { extern love::graphics::Graphics *createInstance(); }
+#endif
+
+Graphics *Graphics::createInstance(const std::vector<Renderer> &renderers)
+{
+	Graphics *instance = Module::getInstance<Graphics>(M_GRAPHICS);
+
+	if (instance != nullptr)
+		instance->retain();
+	else
+	{
+		for (auto renderer : renderers)
+		{
+			if (renderer == RENDERER_OPENGL)
+				instance = opengl::createInstance();
+#if defined(LOVE_MACOS) || defined(LOVE_IOS)
+			if (renderer == RENDERER_METAL)
+				instance = metal::createInstance();
+#endif
+
+			if (instance != nullptr)
+				break;
+		}
+	}
+
+	return instance;
+}
+
 Graphics::Graphics()
 	: width(0)
 	, height(0)
@@ -241,7 +272,7 @@ ShaderStage *Graphics::newShaderStage(ShaderStage::StageType stage, const std::s
 
 	if (s == nullptr)
 	{
-		s = newShaderStageInternal(stage, cachekey, source, getRenderer() == RENDERER_OPENGLES);
+		s = newShaderStageInternal(stage, cachekey, source, usesGLSLES());
 		if (!cachekey.empty())
 			cachedShaderStages[stage][cachekey] = s;
 	}

src/modules/graphics/Graphics.h

@@ -151,7 +151,7 @@ public:
 	enum Renderer
 	{
 		RENDERER_OPENGL = 0,
-		RENDERER_OPENGLES,
+		RENDERER_METAL,
 		RENDERER_MAX_ENUM
 	};
 
@@ -797,6 +797,11 @@ public:
 	 **/
 	virtual Renderer getRenderer() const = 0;
 
+	/**
+	 * Whether shaders will use GLSL ES or not (mobile shaders).
+	 **/
+	virtual bool usesGLSLES() const = 0;
+
 	/**
 	 * Returns system-dependent renderer information.
 	 * Returned strings can vary greatly between systems! Do not rely on it for
@@ -853,6 +858,8 @@ public:
 		return (T *) scratchBuffer.data();
 	}
 
+	static Graphics *createInstance(const std::vector<Renderer> &renderers);
+
 	static bool getConstant(const char *in, DrawMode &out);
 	static bool getConstant(DrawMode in, const char *&out);
 	static std::vector<std::string> getConstants(DrawMode);

src/modules/graphics/metal/Graphics.h

@@ -88,6 +88,7 @@ public:
 	bool isCanvasFormatSupported(PixelFormat format, bool readable) const override;
 	bool isImageFormatSupported(PixelFormat format, bool sRGB) const override;
 	Renderer getRenderer() const override;
+	bool usesGLSLES() const override;
 	RendererInfo getRendererInfo() const override;
 
 	Shader::Language getShaderLanguageTarget() const override;

src/modules/graphics/metal/Graphics.mm

@@ -133,6 +133,22 @@ static MTLBlendFactor getMTLBlendFactor(BlendFactor factor)
 	return MTLBlendFactorZero;
 }
 
+love::graphics::Graphics *createInstance()
+{
+	love::graphics::Graphics *instance = nullptr;
+
+	try
+	{
+		instance = new Graphics();
+	}
+	catch (love::Exception &e)
+	{
+		printf("Cannot create Metal renderer: %s\n", e.what());
+	}
+
+	return instance;
+}
+
 Graphics::Graphics()
 	: device(nil)
 	, commandQueue(nil)
@@ -935,6 +951,30 @@ void Graphics::setBlendState(const BlendState &blend)
 	}
 }
 
+Graphics::Renderer Graphics::getRenderer() const
+{
+	return RENDERER_METAL;
+}
+
+bool Graphics::usesGLSLES() const
+{
+#ifdef LOVE_IOS
+	return true;
+#else
+	return false;
+#endif
+}
+
+Graphics::RendererInfo Graphics::getRendererInfo() const
+{
+	RendererInfo info;
+	info.name = "Metal";
+	info.version = "1"; // TODO
+	info.vendor = ""; // TODO
+	info.device = device.name.UTF8String;
+	return info;
+}
+
 } // metal
 } // graphics
 } // love

src/modules/graphics/opengl/Graphics.cpp

@@ -88,6 +88,22 @@ static GLenum getGLBlendFactor(BlendFactor factor)
 	return 0;
 }
 
+love::graphics::Graphics *createInstance()
+{
+	love::graphics::Graphics *instance = nullptr;
+
+	try
+	{
+		instance = new Graphics();
+	}
+	catch (love::Exception &e)
+	{
+		printf("Cannot create OpenGL renderer: %s\n", e.what());
+	}
+
+	return instance;
+}
+
 Graphics::Graphics()
 	: windowHasStencil(false)
 	, mainVAO(0)
@@ -1322,7 +1338,12 @@ void Graphics::setWireframe(bool enable)
 
 Graphics::Renderer Graphics::getRenderer() const
 {
-	return GLAD_ES_VERSION_2_0 ? RENDERER_OPENGLES : RENDERER_OPENGL;
+	return RENDERER_OPENGL;
+}
+
+bool Graphics::usesGLSLES() const
+{
+	return GLAD_ES_VERSION_2_0;
 }
 
 Graphics::RendererInfo Graphics::getRendererInfo() const

src/modules/graphics/opengl/Graphics.h

@@ -108,6 +108,7 @@ public:
 	bool isCanvasFormatSupported(PixelFormat format, bool readable) const override;
 	bool isImageFormatSupported(PixelFormat format, bool sRGB) const override;
 	Renderer getRenderer() const override;
+	bool usesGLSLES() const override;
 	RendererInfo getRendererInfo() const override;
 
 	Shader::Language getShaderLanguageTarget() const override;

src/modules/graphics/wrap_Graphics.cpp

@@ -1363,7 +1363,7 @@ static int w_getShaderSource(lua_State *L, int startidx, bool gles, std::string
 
 int w_newShader(lua_State *L)
 {
-	bool gles = instance()->getRenderer() == Graphics::RENDERER_OPENGLES;
+	bool gles = instance()->usesGLSLES();
 
 	std::string vertexsource, pixelsource;
 	w_getShaderSource(L, 1, gles, vertexsource, pixelsource);
@@ -3146,13 +3146,22 @@ static const lua_CFunction types[] =
 
 extern "C" int luaopen_love_graphics(lua_State *L)
 {
-	Graphics *instance = instance();
+	Graphics *instance = nullptr;
+
+	{
+		std::vector<Graphics::Renderer> renderers;
+#if defined(LOVE_MACOS) || defined(LOVE_IOS)
+		renderers.push_back(Graphics::RENDERER_METAL);
+#endif
+		renderers.push_back(Graphics::RENDERER_OPENGL);
+		instance = Graphics::createInstance(renderers);
+	}
+
 	if (instance == nullptr)
 	{
-		luax_catchexcept(L, [&](){ instance = new love::graphics::opengl::Graphics(); });
+		printf("Cannot create graphics: no supported renderer on this system.\n");
+		return luaL_error(L, "Cannot create graphics: no supported renderer on this system.");
 	}
-	else
-		instance->retain();
 
 	WrappedModule w;
 	w.module = instance;