Gas changes:

- Separate gas reg writes according to stages
- Related: Properly support C3D_GasAccMax
- Add C3D_GasBeginAcc
- Set correct gas depth function matching depth test in C3Di_EffectBind

Author: fincs

include/c3d/fog.h

@@ -27,9 +27,11 @@ void C3D_FogLutBind(C3D_FogLut* lut);
 
 void GasLut_FromArray(C3D_GasLut* lut, const u32 data[9]);
 
-void C3D_GasAttn(float value);
-void C3D_GasAccMax(float value);
+void C3D_GasBeginAcc(void);
 void C3D_GasDeltaZ(float value);
+
+void C3D_GasAccMax(float value);
+void C3D_GasAttn(float value);
 void C3D_GasLightPlanar(float min, float max, float attn);
 void C3D_GasLightView(float min, float max, float attn);
 void C3D_GasLightDirection(float dotp);

source/base.c

@@ -62,6 +62,7 @@ static void C3Di_AptEventHook(APT_HookType hookType, C3D_UNUSED void* param)
 			C3Di_DirtyUniforms(GPU_GEOMETRY_SHADER);
 
 			ctx->fixedAttribDirty |= ctx->fixedAttribEverDirty;
+			ctx->gasFlags |= C3DiG_BeginAcc | C3DiG_AccStage | C3DiG_RenderStage;
 
 			C3D_LightEnv* env = ctx->lightEnv;
 			if (ctx->fogLut)

source/effect.c

@@ -93,6 +93,7 @@ void C3Di_EffectBind(C3D_Effect* e)
 	GPUCMD_AddWrite(GPUREG_FACECULLING_CONFIG, e->cullMode & 0x3);
 	GPUCMD_AddIncrementalWrites(GPUREG_DEPTHMAP_SCALE, (u32*)&e->zScale, 2);
 	GPUCMD_AddIncrementalWrites(GPUREG_FRAGOP_ALPHA_TEST, (u32*)&e->alphaTest, 4);
+	GPUCMD_AddMaskedWrite(GPUREG_GAS_DELTAZ_DEPTH, 0x8, (u32)GPU_MAKEGASDEPTHFUNC((e->depthTest>>4)&7) << 24);
 	GPUCMD_AddWrite(GPUREG_BLEND_COLOR, e->blendClr);
 	GPUCMD_AddWrite(GPUREG_BLEND_FUNC, e->alphaBlend);
 	GPUCMD_AddWrite(GPUREG_LOGIC_OP, e->clrLogicOp);

source/gas.c

@@ -39,15 +39,26 @@ void GasLut_FromArray(C3D_GasLut* lut, const u32 data[9])
 	}
 }
 
-void C3D_GasAttn(float value)
+void C3D_GasBeginAcc(void)
+{
+	C3D_Context* ctx = C3Di_GetContext();
+
+	if (!(ctx->flags & C3DiF_Active))
+		return;
+
+	ctx->gasFlags |= C3DiG_BeginAcc;
+}
+
+void C3D_GasDeltaZ(float value)
 {
 	C3D_Context* ctx = C3Di_GetContext();
 
 	if (!(ctx->flags & C3DiF_Active))
 		return;
 
 	ctx->flags |= C3DiF_Gas;
-	ctx->gasAttn = f32tof16(value);
+	ctx->gasDeltaZ = (u32)(value*0x100);
+	ctx->gasFlags |= C3DiG_AccStage;
 }
 
 void C3D_GasAccMax(float value)
@@ -59,18 +70,19 @@ void C3D_GasAccMax(float value)
 
 	ctx->flags |= C3DiF_Gas;
 	ctx->gasAccMax = f32tof16(1.0f / value);
+	ctx->gasFlags |= C3DiG_SetAccMax;
 }
 
-void C3D_GasDeltaZ(float value)
+void C3D_GasAttn(float value)
 {
 	C3D_Context* ctx = C3Di_GetContext();
 
 	if (!(ctx->flags & C3DiF_Active))
 		return;
 
 	ctx->flags |= C3DiF_Gas;
-	ctx->gasDeltaZ = (u32)(value*0x100) & 0xFFFFFF;
-	ctx->gasDeltaZ |= 2<<24;
+	ctx->gasAttn = f32tof16(value);
+	ctx->gasFlags |= C3DiG_RenderStage;
 }
 
 void C3D_GasLightPlanar(float min, float max, float attn)
@@ -82,6 +94,7 @@ void C3D_GasLightPlanar(float min, float max, float attn)
 
 	ctx->flags |= C3DiF_Gas;
 	ctx->gasLightXY = conv_u8(min,0) | conv_u8(max,8) | conv_u8(attn,16);
+	ctx->gasFlags |= C3DiG_RenderStage;
 }
 
 void C3D_GasLightView(float min, float max, float attn)
@@ -93,6 +106,7 @@ void C3D_GasLightView(float min, float max, float attn)
 
 	ctx->flags |= C3DiF_Gas;
 	ctx->gasLightZ = conv_u8(min,0) | conv_u8(max,8) | conv_u8(attn,16);
+	ctx->gasFlags |= C3DiG_RenderStage;
 }
 
 void C3D_GasLightDirection(float dotp)
@@ -105,6 +119,7 @@ void C3D_GasLightDirection(float dotp)
 	ctx->flags |= C3DiF_Gas;
 	ctx->gasLightZColor &= ~0xFF;
 	ctx->gasLightZColor |= conv_u8(dotp,0);
+	ctx->gasFlags |= C3DiG_RenderStage;
 }
 
 void C3D_GasLutInput(GPU_GASLUTINPUT input)
@@ -117,6 +132,7 @@ void C3D_GasLutInput(GPU_GASLUTINPUT input)
 	ctx->flags |= C3DiF_Gas;
 	ctx->gasLightZColor &= ~0x100;
 	ctx->gasLightZColor |= (input&1)<<8;
+	ctx->gasFlags |= C3DiG_RenderStage;
 }
 
 void C3D_GasLutBind(C3D_GasLut* lut)
@@ -136,17 +152,25 @@ void C3D_GasLutBind(C3D_GasLut* lut)
 
 void C3Di_GasUpdate(C3D_Context* ctx)
 {
-	//__builtin_printf("updgasstate %08lX\n", ctx->flags);
-	//for(;;);
 	if (ctx->flags & C3DiF_Gas)
 	{
 		ctx->flags &= ~C3DiF_Gas;
-		GPUCMD_AddWrite(GPUREG_GAS_ATTENUATION, ctx->gasAttn);
-		//GPUCMD_AddWrite(GPUREG_GAS_ACCMAX, ctx->gasAccMax);
-		GPUCMD_AddWrite(GPUREG_GAS_LIGHT_XY, ctx->gasLightXY);
-		GPUCMD_AddWrite(GPUREG_GAS_LIGHT_Z, ctx->gasLightZ);
-		GPUCMD_AddWrite(GPUREG_GAS_LIGHT_Z_COLOR, ctx->gasLightZColor);
-		GPUCMD_AddWrite(GPUREG_GAS_DELTAZ_DEPTH, ctx->gasDeltaZ);
+		u32 gasFlags = ctx->gasFlags;
+		ctx->gasFlags = 0;
+
+		if (gasFlags & C3DiG_BeginAcc)
+			GPUCMD_AddMaskedWrite(GPUREG_GAS_ACCMAX_FEEDBACK, 0x3, 0);
+		if (gasFlags & C3DiG_AccStage)
+			GPUCMD_AddMaskedWrite(GPUREG_GAS_DELTAZ_DEPTH, 0x7, ctx->gasDeltaZ);
+		if (gasFlags & C3DiG_SetAccMax)
+			GPUCMD_AddWrite(GPUREG_GAS_ACCMAX, ctx->gasAccMax);
+		if (gasFlags & C3DiG_RenderStage)
+		{
+			GPUCMD_AddWrite(GPUREG_GAS_ATTENUATION, ctx->gasAttn);
+			GPUCMD_AddWrite(GPUREG_GAS_LIGHT_XY, ctx->gasLightXY);
+			GPUCMD_AddWrite(GPUREG_GAS_LIGHT_Z, ctx->gasLightZ);
+			GPUCMD_AddWrite(GPUREG_GAS_LIGHT_Z_COLOR, ctx->gasLightZColor);
+		}
 	}
 	if (ctx->flags & C3DiF_GasLut)
 	{

source/internal.h

@@ -53,7 +53,9 @@ typedef struct
 	C3D_FogLut* fogLut;
 
 	u16 gasAttn, gasAccMax;
-	u32 gasLightXY, gasLightZ, gasLightZColor, gasDeltaZ;
+	u32 gasLightXY, gasLightZ, gasLightZColor;
+	u32 gasDeltaZ : 24;
+	u32 gasFlags : 8;
 	C3D_GasLut* gasLut;
 
 	C3D_ProcTex* procTex;
@@ -98,6 +100,14 @@ enum
 	C3DiF_TexEnvAll = 0x3F << 26,
 };
 
+enum
+{
+	C3DiG_BeginAcc    = BIT(0),
+	C3DiG_AccStage    = BIT(1),
+	C3DiG_SetAccMax   = BIT(2),
+	C3DiG_RenderStage = BIT(3),
+};
+
 static inline C3D_Context* C3Di_GetContext(void)
 {
 	extern C3D_Context __C3D_Context;