🚚 new directive set_attenuation_defaults

Works like all other `set_*_defaults` directives. The arguments are an exact match to the `Ogre::Light::setAttenuation()`, see https://ogrecave.github.io/ogre/api/latest/class_ogre_1_1_light.html#a43f763d809bc7da9a85fec15f57380f4

Parameters:
* **range**	The absolute upper range of the light in world units.
* **constant**	The constant factor in the attenuation formula: 1.0 means never attenuate, 0.0 is complete attenuation.
* **linear**	The linear factor in the attenuation formula: 1 means attenuate evenly over the distance.
* **quadratic**	The quadratic factor in the attenuation formula: adds a curvature to the attenuation formula.

I thoroughly verified using debugger that the values do propagate to the OGRE light source and stay there. I wasn't able to see any effect though. Let's test under OGRE 14.

source/main/gfx/GfxData.h

@@ -117,6 +117,12 @@ static const int CAMERA_MODE_ALWAYS_HIDDEN = -3;
 static const int CAMERA_MODE_ALWAYS_VISIBLE = -2;
 static const int CAMERA_MODE_3RDPERSON_ONLY = -1;
 
+// Light attenuation defaults - matches defaults in `Ogre::Light::Light()` constructor.
+static const float ATTENUATION_DEFAULT_RANGE_METERS = 250.f;   //!< The absolute upper range of the light in meters.
+static const float ATTENUATION_DEFAULT_CONSTANT_FACTOR = 1.f;  //!< The constant factor in the attenuation formula: 1.0 means never attenuate, 0.0 is complete attenuation.
+static const float ATTENUATION_DEFAULT_LINEAR_FACTOR = 0.f;    //!< The linear factor in the attenuation formula: 1 means attenuate evenly over the distance.
+static const float ATTENUATION_DEFAULT_QUADRATIC_FACTOR = 0.f; //!< The quadratic factor in the attenuation formula: adds a curvature to the attenuation formula. 
+
 enum ShifterPropAnim
 {
     SHIFTER_INVALID = 0,

source/main/physics/ActorSpawner.cpp

@@ -1997,6 +1997,13 @@ void ActorSpawner::ProcessFlare3(RigDef::Flare3 & def)
     flare_t& f = m_actor->ar_flares.back();
     f.uses_inertia = true;
     this->_ProcessSimpleInertia(*def.inertia_defaults, f.inertia);
+
+    // Also apply attenuation settings
+    f.light->setAttenuation(
+        def.attenuation_defaults->range,
+        def.attenuation_defaults->constant,
+        def.attenuation_defaults->linear,
+        def.attenuation_defaults->quadratic);
 }
 
 void ActorSpawner::ProcessFlare2(RigDef::Flare2 & def)

source/main/resources/rig_def_fileformat/RigDef_File.h

@@ -148,6 +148,7 @@ enum class Keyword
     SCRIPTS,
     SECTION,
     SECTIONCONFIG,
+    SET_ATTENUATION_DEFAULTS,
     SET_BEAM_DEFAULTS,
     SET_BEAM_DEFAULTS_SCALE,
     SET_COLLISION_RANGE,
@@ -406,6 +407,16 @@ struct AeroAnimator // used by Animator
     unsigned int engine_idx = 0u;
 };
 
+/// Sets the attenuation parameters of the light source i.e. how it diminishes with distance.
+/// See `Ogre::Light::setAttenuation()` - https://ogrecave.github.io/ogre/api/latest/class_ogre_1_1_light.html#a43f763d809bc7da9a85fec15f57380f4
+struct AttenuationDefaults // used by Flare3
+{
+    float range     = RoR::ATTENUATION_DEFAULT_RANGE_METERS;     //!< The absolute upper range of the light in meters.
+    float constant  = RoR::ATTENUATION_DEFAULT_CONSTANT_FACTOR;  //!< The constant factor in the attenuation formula: 1.0 means never attenuate, 0.0 is complete attenuation.
+    float linear    = RoR::ATTENUATION_DEFAULT_LINEAR_FACTOR;    //!< The linear factor in the attenuation formula: 1 means attenuate evenly over the distance.
+    float quadratic = RoR::ATTENUATION_DEFAULT_QUADRATIC_FACTOR; //!< The quadratic factor in the attenuation formula: adds a curvature to the attenuation formula. 
+};
+
 struct BaseWheel
 {
     float width = 0.f;
@@ -882,6 +893,7 @@ struct Flare2 // Used for both 'flares' and 'flares2' sections
 struct Flare3: public Flare2
 {
     std::shared_ptr<Inertia> inertia_defaults;
+    std::shared_ptr<AttenuationDefaults> attenuation_defaults;
 };
 
 struct Flexbody

source/main/resources/rig_def_fileformat/RigDef_Parser.cpp

@@ -30,6 +30,7 @@
 #include "SimConstants.h"
 #include "CacheSystem.h"
 #include "Console.h"
+#include "GfxData.h"
 #include "RigDef_File.h"
 #include "RigDef_Regexes.h"
 #include "Utils.h"
@@ -166,6 +167,9 @@ void Parser::ProcessCurrentLine()
         case Keyword::SECTION:
             this->ParseDirectiveSection();
             return;
+        case Keyword::SET_ATTENUATION_DEFAULTS:
+            this->ParseDirectiveSetAttenuationDefaults();
+            return;
         case Keyword::SET_BEAM_DEFAULTS:
             this->ParseDirectiveSetBeamDefaults();
             return;
@@ -544,6 +548,24 @@ void Parser::ParseDirectiveSetManagedMaterialsOptions()
     m_current_managed_material_options.double_sided = (this->GetArgChar(1) != '0');
 }
 
+void Parser::ParseDirectiveSetAttenuationDefaults()
+{
+    // Get values from the text file
+    float range = this->GetArgFloat(1);
+    float constant      = (m_num_args > 2) ? this->GetArgFloat(2) : -1;
+    float linear        = (m_num_args > 3) ? this->GetArgFloat(3) : -1;
+    float quadratic     = (m_num_args > 4) ? this->GetArgFloat(4) : -1;
+
+    // Create a 'preset' object as a clone of previous preset object.
+    m_user_attenuation_defaults = std::shared_ptr<AttenuationDefaults>(new AttenuationDefaults(*m_user_attenuation_defaults));
+
+    // Update the preset values. If -1 then reset to builtin constant.
+    m_user_attenuation_defaults->range     = (range     < 0) ? ATTENUATION_DEFAULT_RANGE_METERS     : range;
+    m_user_attenuation_defaults->constant  = (constant  < 0) ? ATTENUATION_DEFAULT_CONSTANT_FACTOR  : constant; 
+    m_user_attenuation_defaults->linear    = (linear    < 0) ? ATTENUATION_DEFAULT_LINEAR_FACTOR    : linear;   
+    m_user_attenuation_defaults->quadratic = (quadratic < 0) ? ATTENUATION_DEFAULT_QUADRATIC_FACTOR : quadratic;
+}
+
 void Parser::ParseDirectiveSetBeamDefaultsScale()
 {
     if (! this->CheckNumArguments(5)) { return; }
@@ -964,11 +986,11 @@ void Parser::ParseFlaresUnified()
 
 void Parser::ParseFlares3()
 {
-    const bool is_flares2 = (m_current_block == Keyword::FLARES2);
-    if (! this->CheckNumArguments(is_flares2 ? 6 : 5)) { return; }
+    if (! this->CheckNumArguments(6)) { return; }
 
     Flare3 flare3;
     flare3.inertia_defaults = m_user_default_inertia;
+    flare3.attenuation_defaults = m_user_attenuation_defaults;
 
     flare3.reference_node = this->GetArgNodeRef(0);
     flare3.node_axis_x    = this->GetArgNodeRef(1);
@@ -2705,6 +2727,8 @@ void Parser::Prepare()
     m_user_beam_defaults->breaking_threshold    = BEAM_BREAK;
     m_user_beam_defaults->visual_beam_diameter  = DEFAULT_BEAM_DIAMETER;
 
+    m_user_attenuation_defaults = std::shared_ptr<AttenuationDefaults>(new AttenuationDefaults);
+
     m_root_module = m_definition->root_module;
     m_current_module = m_definition->root_module;
 

source/main/resources/rig_def_fileformat/RigDef_Parser.h

@@ -97,6 +97,7 @@ class Parser
     void ParseDirectivePropCameraMode();
     void ParseDirectiveSection();
     void ParseDirectiveSectionConfig();
+    void ParseDirectiveSetAttenuationDefaults();
     void ParseDirectiveSetBeamDefaults();
     void ParseDirectiveSetBeamDefaultsScale();
     void ParseDirectiveSetDefaultMinimass();
@@ -257,6 +258,7 @@ class Parser
     // Data from user directives
     // Each affected section-struct has a shared_ptr to it's respective defaults
     std::shared_ptr<Inertia>             m_user_default_inertia;
+    std::shared_ptr<AttenuationDefaults> m_user_attenuation_defaults;
     std::shared_ptr<BeamDefaults>        m_user_beam_defaults;
     std::shared_ptr<NodeDefaults>        m_user_node_defaults;
     std::shared_ptr<DefaultMinimass>     m_set_default_minimass;

source/main/resources/rig_def_fileformat/RigDef_Regexes.h

@@ -2,7 +2,7 @@
     This source file is part of Rigs of Rods
     Copyright 2005-2012 Pierre-Michel Ricordel
     Copyright 2007-2012 Thomas Fischer
-    Copyright 2013-2020 Petr Ohlidal
+    Copyright 2013-2023 Petr Ohlidal
 
     For more information, see http://www.rigsofrods.org/
 
@@ -200,6 +200,7 @@ namespace Regexes
     E_KEYWORD_BLOCK("scripts")                                    \
     E_KEYWORD_INLINE("section")                                   \
     E_KEYWORD_INLINE("sectionconfig")                             \
+    E_KEYWORD_INLINE("set_attenuation_defaults")                  \
     E_KEYWORD_INLINE("set_beam_defaults")                         \
     E_KEYWORD_INLINE("set_beam_defaults_scale")                   \
     E_KEYWORD_INLINE("set_collision_range")                       \