pikuma_ps1/code/gte_hello/hello_gte_tape.c

#ifdef INTELLISENSE_DIRECTIVES
#	include "duffle/gen/duffle.macs.h"
#	include "duffle/gen/duffle.offsets.h"
#	include "duffle/atom_dsl.h"
#	include "duffle/lottes_tape.h"
#	include "duffle/word_count.metadata.h"
#	include "gen/gte_hello.offsets.h"
#	include "hello_gte.h"
#endif

#pragma region MACs (Mips Atom components)



#pragma endregion MACs

#pragma region Baked Atoms

typedef Struct_(Binds_CubeTri) {
	U4     PrimCursor;
	V4_S2* FaceCursor;
	V3_S2* VertBase;
	U4*    OtBase;
};
internal MipsAtom_(rbind_cube_g4_face) atom_info(atom_bind(Binds_CubeTri)
,	atom_reads(R_TapePtr)
,	atom_writes(R_PrimCursor, R_FaceCursor, R_VertBase, R_OtBase)
){
	/* Pop 4 arguments from the tape directly into the workspace registers */
	load_word(R_PrimCursor, R_TapePtr, O_(Binds_CubeTri,PrimCursor)), 
	load_word(R_FaceCursor, R_TapePtr, O_(Binds_CubeTri,FaceCursor)), 
	load_word(R_VertBase,   R_TapePtr, O_(Binds_CubeTri,VertBase)), 
	load_word(R_OtBase,     R_TapePtr, O_(Binds_CubeTri,OtBase)), 
	add_ui_self(            R_TapePtr, S_(Binds_CubeTri)),
	mac_yield()
};

/* ============================================================================
 *  cube_g4_face — Draw one cube face (Gouraud-shaded quad) via the GTE tape pipeline
 * ============================================================================
 *  Reads 4 indices from R_FaceCur (V4_S2 = 8 bytes), loads 4 vertices into
 *  the GTE, runs the PsyQ RotAverageNclip4 sequence, and renders a Poly_G4.
 */
internal 
MipsAtom_(cube_g4_face) atom_info(
		atom_reads( R_PrimCursor, R_FaceCursor, R_VertBase, R_OtBase),
		atom_writes(R_PrimCursor, R_FaceCursor)
){
	load_half_u(R_T0, R_FaceCursor, 0 * S_(S2)),
	load_half_u(R_T1, R_FaceCursor, 1 * S_(S2)),
	load_half_u(R_T2, R_FaceCursor, 2 * S_(S2)),
	load_half_u(R_T3, R_FaceCursor, 3 * S_(S2)),

	mac_gte_load_tri_verts(R_T0, R_T1, R_T2),
	nop2, gte_cmdw_rotate_translate_perspective_triple,
	nop2, gte_cmdw_nclip,

	nop2,  gte_mv_from_data_r(R_T0, C2_MAC0),
	nop,
	branch_le_zero(R_T0, atom_offset(cull, cube_g4_face_exit)), nop,

	store_word(R_0, R_PrimCursor, O_(Poly_G4, tag)),
	mac_format_g4_color(
		/* c0 magenta */ 0xFF, 0x00, 0xFF,
		/* c1 yellow  */ 0xFF, 0xFF, 0x00,
		/* c2 cyan    */ 0x00, 0xFF, 0xFF,
		/* c3 green   */ 0x00, 0xFF, 0x00),
	mac_gte_store_g4_p012_post_rtpt_pre_rtps(),

	shift_lleft(R_AT, R_T3, v3s2_byteoff), add_u(R_AT, R_AT, R_VertBase),
	load_word(R_V0, R_AT, O_(V3_S2, x)),   load_word(R_V1, R_AT, O_(V3_S2, z)),
	gte_mv_to_data_r(R_V0, C2_VXY0),       gte_mv_to_data_r(R_V1, C2_VZ0),

	nop2, gte_cmdw_rotate_translate_perspective_single,
	mac_gte_store_g4_p3_post_rtps(),

	nop2, gte_cmdw_avg_sort_z4,
	nop2, gte_mv_from_data_r(R_T1, C2_OTZ),

	add_ui(      R_AT, R_0,  OrderingTbl_Len),
	set_lt_u(    R_AT, R_T1, R_AT),
	branch_equal(R_AT, R_0,  atom_offset(bounds_chk, cube_g4_face_exit)), nop,
	mac_insert_ot_tag_g4(),

atom_label(cube_g4_face_exit)
	add_ui_self(R_PrimCursor, S_(Poly_G4)),     /* 9 words = Poly_G4 */
	add_ui_self(R_FaceCursor, S_(S2) * 4),      /* 4 × S2 = 8 bytes */
	mac_yield()
};

typedef Struct_(Binds_FloorTri) {
	U4     PrimCursor;
	V3_S2* FaceCursor;
	V3_S2* VertBase;
	U4*    OtBase;
};
internal 
MipsAtom_(rbind_floor_f3_face) atom_info(atom_bind(Binds_FloorTri)
	, atom_reads(R_TapePtr)
	, atom_writes(R_PrimCursor, R_FaceCursor, R_VertBase, R_OtBase)
){
	/* Pop 4 arguments from the tape directly into the workspace registers */
	load_word(R_PrimCursor, R_TapePtr, O_(Binds_FloorTri,PrimCursor)), 
	load_word(R_FaceCursor, R_TapePtr, O_(Binds_FloorTri,FaceCursor)), 
	load_word(R_VertBase,   R_TapePtr, O_(Binds_FloorTri,VertBase)), 
	load_word(R_OtBase,     R_TapePtr, O_(Binds_FloorTri,OtBase)), 
	add_ui_self(            R_TapePtr, S_(Binds_FloorTri)),
	mac_yield()
};

internal 
MipsAtom_(floor_f3_face) atom_info(
	, atom_reads( R_PrimCursor, R_FaceCursor, R_VertBase, R_OtBase)
	, atom_writes(R_PrimCursor, R_FaceCursor)
) {
	mac_load_tri_indices(  R_T0, R_T1, R_T2),
	mac_gte_load_tri_verts(R_T0, R_T1, R_T2),
	nop2, gte_cmdw_rotate_translate_perspective_triple,
	nop2, gte_cmdw_nclip,
 
	/* Culling (Branch forward if Backface) */
	nop2, gte_mv_from_data_r(R_T0, C2_MAC0),
	nop,
	branch_le_zero(R_T0, atom_offset(culling, floor_f3_face_exit)), nop,
	/* Format Primitive */
	mac_format_f3_color(0xFF, 0xFF, 0xFF),  // RGB-form (R=FF, G=FF, B=FF = white)
	mac_gte_store_f3_post_rtpt(),
	
	/* Calculate Depth */
	nop2, gte_avg_sort_z3,            
	nop2, gte_mv_from_data_r(R_T1, C2_OTZ),      
	/* Bounds Check OTZ < 2048 (Branch forward to skip insertion) */
	add_ui(      R_AT, R_0,  OrderingTbl_Len),   
	set_lt_u(    R_AT, R_T1, R_AT), 
	branch_equal(R_AT, R_0,  atom_offset(bounds_chk, floor_f3_face_exit)), nop, 
	/* Insert into Ordering Table Linked List */
	mac_insert_ot_tag_f3(),
	add_ui_self(R_PrimCursor, S_(Poly_F3)), /* Advance Prim Cursor (5 words) */
		// Note(Ed): No bounds checking, should be checked before atom runs.

/* Advance Input Cursor & Yield (Both branch targets land here) */
atom_label(floor_f3_face_exit) 
	add_ui_self(R_FaceCursor, S_(S2) * 4),  /* Advance Face Cursor (4 * S2 = 8 bytes) */
	mac_yield()
};

typedef Struct_(Binds_SyncPrimitiveArena) { U4 used; U4 cursor; };
internal MipsAtom_(sync_primitive_arena) atom_info(atom_bind(Binds_SyncPrimitiveArena)
	, atom_reads( R_TapePtr, R_PrimCursor)
	, atom_writes(R_TapePtr)
){
	load_word(R_AT, R_TapePtr, O_(Binds_SyncPrimitiveArena,used)),
	load_word(R_T0, R_TapePtr, O_(Binds_SyncPrimitiveArena,cursor)),      
	add_ui_self(    R_TapePtr, S_(Binds_SyncPrimitiveArena)),
	/* Calculate byte offset and store directly back to RAM */
	sub_u(     R_T0, R_PrimCursor, R_T0), // R_T0    = R_PrimCursor - binds.cursor
	store_word(R_T0, R_AT, 0),            // R_AT[0] = R_T0
	mac_yield()
};

#pragma endregion Baked Atoms