Improve ergonomics of CachedShaderSetting

src/client/game.cpp

@@ -398,7 +398,7 @@ class GameGlobalShaderConstantSetter : public IShaderConstantSetter
 	CachedPixelShaderSetting<SamplerLayer_t> m_texture3{"texture3"};
 	CachedVertexShaderSetting<float, 2> m_texel_size0_vertex{"texelSize0"};
 	CachedPixelShaderSetting<float, 2> m_texel_size0_pixel{"texelSize0"};
-	std::array<float, 2> m_texel_size0_values;
+	v2f m_texel_size0;
 	CachedStructPixelShaderSetting<float, 7> m_exposure_params_pixel{
 		"exposureParams",
 		std::array<const char*, 7> {
@@ -477,10 +477,7 @@ public:
 	void onSetConstants(video::IMaterialRendererServices *services) override
 	{
 		video::SColorf fogcolorf(m_sky->getFogColor());
-		float fogcolorfa[4] = {
-			fogcolorf.r, fogcolorf.g, fogcolorf.b, fogcolorf.a,
-		};
-		m_fog_color.set(fogcolorfa, services);
+		m_fog_color.set(fogcolorf, services);
 
 		float fog_distance = 10000 * BS;
 		if (m_fog_enabled && !*m_force_fog_off)
@@ -494,11 +491,7 @@ public:
 		u32 daynight_ratio = (float)m_client->getEnv().getDayNightRatio();
 		video::SColorf sunlight;
 		get_sunlight_color(&sunlight, daynight_ratio);
-		float dnc[3] = {
-			sunlight.r,
-			sunlight.g,
-			sunlight.b };
-		m_day_light.set(dnc, services);
+		m_day_light.set(sunlight, services);
 
 		video::SColorf star_color = m_sky->getCurrentStarColor();
 		float clr[4] = {star_color.r, star_color.g, star_color.b, star_color.a};
@@ -513,24 +506,18 @@ public:
 		m_animation_timer_delta_vertex.set(&animation_timer_delta_f, services);
 		m_animation_timer_delta_pixel.set(&animation_timer_delta_f, services);
 
-		float eye_position_array[3];
 		v3f epos = m_client->getEnv().getLocalPlayer()->getEyePosition();
-		epos.getAs3Values(eye_position_array);
-		m_eye_position_pixel.set(eye_position_array, services);
-		m_eye_position_vertex.set(eye_position_array, services);
+		m_eye_position_pixel.set(epos, services);
+		m_eye_position_vertex.set(epos, services);
 
 		if (m_client->getMinimap()) {
-			float minimap_yaw_array[3];
 			v3f minimap_yaw = m_client->getMinimap()->getYawVec();
-			minimap_yaw.getAs3Values(minimap_yaw_array);
-			m_minimap_yaw.set(minimap_yaw_array, services);
+			m_minimap_yaw.set(minimap_yaw, services);
 		}
 
-		float camera_offset_array[3];
 		v3f offset = intToFloat(m_client->getCamera()->getOffset(), BS);
-		offset.getAs3Values(camera_offset_array);
-		m_camera_offset_pixel.set(camera_offset_array, services);
-		m_camera_offset_vertex.set(camera_offset_array, services);
+		m_camera_offset_pixel.set(offset, services);
+		m_camera_offset_vertex.set(offset, services);
 
 		SamplerLayer_t tex_id;
 		tex_id = 0;
@@ -542,8 +529,8 @@ public:
 		tex_id = 3;
 		m_texture3.set(&tex_id, services);
 
-		m_texel_size0_vertex.set(m_texel_size0_values.data(), services);
-		m_texel_size0_pixel.set(m_texel_size0_values.data(), services);
+		m_texel_size0_vertex.set(m_texel_size0, services);
+		m_texel_size0_pixel.set(m_texel_size0, services);
 
 		const AutoExposure &exposure_params = m_client->getEnv().getLocalPlayer()->getLighting().exposure;
 		std::array<float, 7> exposure_buffer = {
@@ -577,14 +564,12 @@ public:
 				transform.transformVect(sun_position);
 				sun_position.normalize();
 
-				float sun_position_array[3] = { sun_position.X, sun_position.Y, sun_position.Z};
-				m_sun_position_pixel.set(sun_position_array, services);
+				m_sun_position_pixel.set(sun_position, services);
 
 				float sun_brightness = rangelim(107.143f * m_sky->getSunDirection().dotProduct(v3f(0.f, 1.f, 0.f)), 0.f, 1.f);
 				m_sun_brightness_pixel.set(&sun_brightness, services);
 			} else {
-				float sun_position_array[3] = { 0.f, 0.f, -1.f };
-				m_sun_position_pixel.set(sun_position_array, services);
+				m_sun_position_pixel.set(v3f(0.f, 0.f, -1.f), services);
 
 				float sun_brightness = 0.f;
 				m_sun_brightness_pixel.set(&sun_brightness, services);
@@ -596,15 +581,12 @@ public:
 				transform.transformVect(moon_position);
 				moon_position.normalize();
 
-				float moon_position_array[3] = { moon_position.X, moon_position.Y, moon_position.Z};
-				m_moon_position_pixel.set(moon_position_array, services);
+				m_moon_position_pixel.set(moon_position, services);
 
 				float moon_brightness = rangelim(107.143f * m_sky->getMoonDirection().dotProduct(v3f(0.f, 1.f, 0.f)), 0.f, 1.f);
 				m_moon_brightness_pixel.set(&moon_brightness, services);
-			}
-			else {
-				float moon_position_array[3] = { 0.f, 0.f, -1.f };
-				m_moon_position_pixel.set(moon_position_array, services);
+			} else {
+				m_moon_position_pixel.set(v3f(0.f, 0.f, -1.f), services);
 
 				float moon_brightness = 0.f;
 				m_moon_brightness_pixel.set(&moon_brightness, services);
@@ -619,12 +601,9 @@ public:
 		video::ITexture *texture = material.getTexture(0);
 		if (texture) {
 			core::dimension2du size = texture->getSize();
-			m_texel_size0_values[0] = 1.f / size.Width;
-			m_texel_size0_values[1] = 1.f / size.Height;
-		}
-		else {
-			m_texel_size0_values[0] = 0.f;
-			m_texel_size0_values[1] = 0.f;
+			m_texel_size0 = v2f(1.f / size.Width, 1.f / size.Height);
+		} else {
+			m_texel_size0 = v2f();
 		}
 	}
 };

src/client/shader.cpp

@@ -227,7 +227,7 @@ public:
 
 		// Set world matrix
 		core::matrix4 world = driver->getTransform(video::ETS_WORLD);
-		m_world.set(*reinterpret_cast<float(*)[16]>(world.pointer()), services);
+		m_world.set(world, services);
 
 		// Set clip matrix
 		core::matrix4 worldView;
@@ -237,12 +237,12 @@ public:
 		core::matrix4 worldViewProj;
 		worldViewProj = driver->getTransform(video::ETS_PROJECTION);
 		worldViewProj *= worldView;
-		m_world_view_proj.set(*reinterpret_cast<float(*)[16]>(worldViewProj.pointer()), services);
+		m_world_view_proj.set(worldViewProj, services);
 
 		if (driver->getDriverType() == video::EDT_OGLES2 || driver->getDriverType() == video::EDT_OPENGL3) {
 			core::matrix4 texture = driver->getTransform(video::ETS_TEXTURE_0);
-			m_world_view.set(*reinterpret_cast<float(*)[16]>(worldView.pointer()), services);
-			m_texture.set(*reinterpret_cast<float(*)[16]>(texture.pointer()), services);
+			m_world_view.set(worldView, services);
+			m_texture.set(texture, services);
 		}
 	}
 };

src/client/shader.h

@@ -105,6 +105,57 @@ public:
 			has_been_set = true;
 		}
 	}
+
+	/* Type specializations */
+
+	/*
+	 * T2 looks redundant here but it is necessary so the compiler won't
+	 * resolve the templates at class instantiation and then fail because
+	 * some of these methods don't have valid types (= are not usable).
+	 * ref: <https://stackoverflow.com/a/6972771>
+	 *
+	 * Note: a `bool dummy` template parameter would have been easier but MSVC
+	 * does not like that. Also make sure not to define different specializations
+	 * with the same parameters, MSVC doesn't like that either.
+	 * I extend my thanks to Microsoft®
+	 */
+#define SPECIALIZE(_type, _count_expr) \
+	template<typename T2 = T> \
+	std::enable_if_t<std::is_same_v<T, T2> && std::is_same_v<T2, _type> && (_count_expr)>
+
+	SPECIALIZE(float, count == 2)
+	set(const v2f value, video::IMaterialRendererServices *services)
+	{
+		float array[2] = { value.X, value.Y };
+		set(array, services);
+	}
+
+	SPECIALIZE(float, count == 3)
+	set(const v3f value, video::IMaterialRendererServices *services)
+	{
+		float array[3] = { value.X, value.Y, value.Z };
+		set(array, services);
+	}
+
+	SPECIALIZE(float, count == 3 || count == 4)
+	set(const video::SColorf value, video::IMaterialRendererServices *services)
+	{
+		if constexpr (count == 3) {
+			float array[3] = { value.r, value.g, value.b };
+			set(array, services);
+		} else {
+			float array[4] = { value.r, value.g, value.b, value.a };
+			set(array, services);
+		}
+	}
+
+	SPECIALIZE(float, count == 16)
+	set(const core::matrix4 &value, video::IMaterialRendererServices *services)
+	{
+		set(value.pointer(), services);
+	}
+
+#undef SPECIALIZE
 };
 
 template <typename T, std::size_t count = 1, bool cache=true>

src/client/shadows/shadowsshadercallbacks.cpp

@@ -32,9 +32,7 @@ void ShadowConstantSetter::onSetConstants(video::IMaterialRendererServices *serv
 	shadowViewProj *= light.getViewMatrix();
 	m_shadow_view_proj.set(shadowViewProj.pointer(), services);
 
-	f32 v_LightDirection[3];
-	light.getDirection().getAs3Values(v_LightDirection);
-	m_light_direction.set(v_LightDirection, services);
+	m_light_direction.set(light.getDirection(), services);
 
 	f32 TextureResolution = light.getMapResolution();
 	m_texture_res.set(&TextureResolution, services);
@@ -79,7 +77,7 @@ void ShadowDepthShaderCB::OnSetConstants(
 
 	lightMVP *= driver->getTransform(video::ETS_WORLD);
 
-	m_light_mvp_setting.set(lightMVP.pointer(), services);
+	m_light_mvp_setting.set(lightMVP, services);
 	m_map_resolution_setting.set(&MapRes, services);
 	m_max_far_setting.set(&MaxFar, services);
 	s32 TextureId = 0;