A_ChangeModeldef

-Added A_ChangeModelDef
A_ChangeModel(modeldef, modelpath, model, modelindex, skinpath, skin, skinid, flags)

This can change the modeldef, model and skins of an actor.

Currently, modelindex and skinindex accept indices from 0-15.

An actor MUST have a modeldef in order to use this function, either defined from modeldef, or given one through the modeldef parameter. You can pass "" to use the same modeldef. Likewise, passing "" for model or skin will just revert to the default model.

Available flags:
CMDL_WEAPONTOPLAYER - If used on a weapon, this instead change's the model on the player instead.

One issue I am aware of right now is that clearing a model by "" sort of works but is buggy. For now you can just manually set the model back using the names explicitly. However, I am stumped and I think getting more eyes on it would help.

src/playsim/actor.h

@@ -1068,6 +1068,9 @@ public:
 	DVector3		WorldOffset;
 	double			Speed;
 	double			FloatSpeed;
+	FName			modelDef;
+	int				models[16] = { -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 }; //[SM] - I hate this solution, but it get's the job done
+	FTextureID		skins[16];
 
 // interaction info
 	FBlockNode		*BlockNode;			// links in blocks (if needed)

src/playsim/p_actionfunctions.cpp

@@ -69,6 +69,7 @@
 #include "sbar.h"
 #include "actorinlines.h"
 #include "types.h"
+#include "model.h"
 
 static FRandom pr_camissile ("CustomActorfire");
 static FRandom pr_cabullet ("CustomBullet");
@@ -5020,6 +5021,46 @@ DEFINE_ACTION_FUNCTION(AActor, A_SetMugshotState)
 	return 0;
 }
 
+//==========================================================================
+//
+// A_ChangeModel(modeldef, modelpath, model, modelindex, skinpath, skin, skinid, flags)
+//
+// This function allows the changing of an actor's modeldef, or models and/or skins at a given index
+//==========================================================================
+
+enum ChangeModelFlags
+{
+	CMDL_WEAPONTOPLAYER = 1
+};
+
+DEFINE_ACTION_FUNCTION(AActor, A_ChangeModel)
+{
+	PARAM_ACTION_PROLOGUE(AActor);
+	PARAM_NAME(modeldef)
+	PARAM_STRING_VAL(modelpath)
+	PARAM_NAME(model)
+	PARAM_INT(modelindex)
+	PARAM_STRING_VAL(skinpath)
+	PARAM_NAME(skin)
+	PARAM_INT(skinindex)
+	PARAM_INT(flags)
+
+	if (self == nullptr)
+		ACTION_RETURN_BOOL(false);
+
+	AActor* mobj = ACTION_CALL_FROM_PSPRITE() && (flags & CMDL_WEAPONTOPLAYER) ? self : stateowner;
+
+	if (modelpath[(int)modelpath.Len() - 1] != '/') modelpath += '/';
+	if (skinpath[(int)skinpath.Len() - 1] != '/') skinpath += '/';
+
+	mobj->hasmodel = modeldef == nullptr && !mobj->hasmodel ? 1 : 0;
+	mobj->modelDef = modeldef;
+	mobj->models[modelindex] = model != nullptr ? FindModel(modelpath.GetChars(), model.GetChars()) : -1;
+	mobj->skins[skinindex] = skin != nullptr ? LoadSkin(skinpath.GetChars(), skin.GetChars()) : mobj->skins[skinindex] = FNullTextureID();
+
+	return 0;
+}
+
 // This needs to account for the fact that internally renderstyles are stored as a series of operations, 
 // but the script side only cares about symbolic constants.
 DEFINE_ACTION_FUNCTION(AActor, GetRenderStyle)

src/r_data/models.cpp

@@ -55,7 +55,7 @@ EXTERN_CVAR (Bool, r_drawvoxels)
 extern TDeletingArray<FVoxel *> Voxels;
 extern TDeletingArray<FVoxelDef *> VoxelDefs;
 
-void RenderFrameModels(FModelRenderer* renderer, FLevelLocals* Level, const FSpriteModelFrame* smf, const FState* curState, const int curTics, const PClass* ti, int translation);
+void RenderFrameModels(FModelRenderer* renderer, FLevelLocals* Level, const FSpriteModelFrame* smf, const FState* curState, const int curTics, const PClass* ti, int translation, AActor* actor);
 
 
 void RenderModel(FModelRenderer *renderer, float x, float y, float z, FSpriteModelFrame *smf, AActor *actor, double ticFrac)
@@ -176,14 +176,14 @@ void RenderModel(FModelRenderer *renderer, float x, float y, float z, FSpriteMod
 	float orientation = scaleFactorX * scaleFactorY * scaleFactorZ;
 
 	renderer->BeginDrawModel(actor->RenderStyle, smf, objectToWorldMatrix, orientation < 0);
-	RenderFrameModels(renderer, actor->Level, smf, actor->state, actor->tics, actor->GetClass(), translation);
+	RenderFrameModels(renderer, actor->Level, smf, actor->state, actor->tics, actor->modelDef != nullptr ? PClass::FindActor(actor->modelDef) : actor->GetClass(), translation, actor);
 	renderer->EndDrawModel(actor->RenderStyle, smf);
 }
 
 void RenderHUDModel(FModelRenderer *renderer, DPSprite *psp, float ofsX, float ofsY)
 {
 	AActor * playermo = players[consoleplayer].camera;
-	FSpriteModelFrame *smf = psp->Caller != nullptr ? FindModelFrame(psp->Caller->GetClass(), psp->GetSprite(), psp->GetFrame(), false) : nullptr;
+	FSpriteModelFrame *smf = psp->Caller != nullptr ? FindModelFrame(psp->Caller->modelDef != nullptr ? PClass::FindActor(psp->Caller->modelDef) : psp->Caller->GetClass(), psp->GetSprite(), psp->GetFrame(), false) : nullptr;
 
 	// [BB] No model found for this sprite, so we can't render anything.
 	if (smf == nullptr)
@@ -224,11 +224,11 @@ void RenderHUDModel(FModelRenderer *renderer, DPSprite *psp, float ofsX, float o
 	renderer->BeginDrawHUDModel(playermo->RenderStyle, objectToWorldMatrix, orientation < 0);
 	uint32_t trans = psp->GetTranslation() != 0 ? psp->GetTranslation() : 0;
 	if ((psp->Flags & PSPF_PLAYERTRANSLATED)) trans = psp->Owner->mo->Translation;
-	RenderFrameModels(renderer, playermo->Level, smf, psp->GetState(), psp->GetTics(), psp->Caller->GetClass(), trans);
+	RenderFrameModels(renderer, playermo->Level, smf, psp->GetState(), psp->GetTics(), psp->Caller->modelDef != nullptr ? PClass::FindActor(psp->Caller->modelDef) : psp->Caller->GetClass(), trans, psp->Caller);
 	renderer->EndDrawHUDModel(playermo->RenderStyle);
 }
 
-void RenderFrameModels(FModelRenderer *renderer, FLevelLocals *Level, const FSpriteModelFrame *smf, const FState *curState, const int curTics, const PClass *ti, int translation)
+void RenderFrameModels(FModelRenderer *renderer, FLevelLocals *Level, const FSpriteModelFrame *smf, const FState *curState, const int curTics, const PClass *ti, int translation, AActor* actor)
 {
 	// [BB] Frame interpolation: Find the FSpriteModelFrame smfNext which follows after smf in the animation
 	// and the scalar value inter ( element of [0,1) ), both necessary to determine the interpolated frame.
@@ -278,10 +278,12 @@ void RenderFrameModels(FModelRenderer *renderer, FLevelLocals *Level, const FSpr
 
 	for (int i = 0; i < smf->modelsAmount; i++)
 	{
+		if (actor->models[i] != -1)
+			smf->modelIDs[i] = actor->models[i];
 		if (smf->modelIDs[i] != -1)
 		{
 			FModel * mdl = Models[smf->modelIDs[i]];
-			auto tex = smf->skinIDs[i].isValid() ? TexMan.GetGameTexture(smf->skinIDs[i], true) : nullptr;
+			auto tex = actor->skins[i].isValid() ? TexMan.GetGameTexture(actor->skins[i], true)  : smf->skinIDs[i].isValid() ? TexMan.GetGameTexture(smf->skinIDs[i], true) : nullptr;
 			mdl->BuildVertexBuffer(renderer);
 
 			mdl->PushSpriteMDLFrame(smf, i);

src/rendering/hwrenderer/scene/hw_sprites.cpp

@@ -834,7 +834,7 @@ void HWSprite::Process(HWDrawInfo *di, AActor* thing, sector_t * sector, area_t
 		z += fz;
 	}
 
-	modelframe = isPicnumOverride ? nullptr : FindModelFrame(thing->GetClass(), spritenum, thing->frame, !!(thing->flags & MF_DROPPED));
+	modelframe = isPicnumOverride ? nullptr : FindModelFrame(thing->modelDef != nullptr ? PClass::FindActor(thing->modelDef) : thing->GetClass(), spritenum, thing->frame, !!(thing->flags & MF_DROPPED));
 
 	// don't bother drawing sprite shadows if this is a model (it will never look right)
 	if (modelframe && isSpriteShadow)

wadsrc/static/zscript/actors/actor.zs

@@ -1132,6 +1132,7 @@ class Actor : Thinker native
 	native void A_SetBlend(color color1, double alpha, int tics, color color2 = 0, double alpha2 = 0.);
 	deprecated("2.3", "Use 'b<FlagName> = [true/false]' instead") native void A_ChangeFlag(string flagname, bool value);
 	native void A_ChangeCountFlags(int kill = FLAG_NO_CHANGE, int item = FLAG_NO_CHANGE, int secret = FLAG_NO_CHANGE);
+	action native void A_ChangeModel(name modeldef, string modelpath = "", name model = "", int modelindex = 0, string skinpath = "", name skin = "", int skinindex = 0, int flags = 0);
 
 	void A_SetFriendly (bool set)
 	{

wadsrc/static/zscript/constants.zs

@@ -365,6 +365,12 @@ enum ERadiusGiveFlags
 	RGF_EITHER		=	1 << 17,
 };
 
+// Change model flags
+enum ChangeModelFlags
+{
+	CMDL_WEAPONTOPLAYER = 1
+};
+
 // Activation flags
 enum EActivationFlags
 {