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dreamcast2: add triangle_ta_fullscreen

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This commit is contained in:
Zack Buhman 2025-08-26 17:07:59 -05:00
parent 18c906133c
commit 9ecb8c6f5f
2 changed files with 271 additions and 1 deletions
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8
dreamcast2/example/example.mk
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@ -14,9 +14,15 @@ TRIANGLE_CORE_OBJ = \
example/triangle_core.elf: LDSCRIPT = $(LIB)/main.lds
example/triangle_core.elf: $(START_OBJ) $(TRIANGLE_CORE_OBJ)
TRIANGLE_TA_OBJ = \
example/triangle_ta.o
example/triangle_ta.elf: LDSCRIPT = $(LIB)/main.lds
example/triangle_ta.elf: $(START_OBJ) $(TRIANGLE_TA_OBJ)
TRIANGLE_TA_FULLSCREEN_OBJ = \
holly/core/region_array.o \
example/triangle_ta_fullscreen.o
example/triangle_ta_fullscreen.elf: LDSCRIPT = $(LIB)/main.lds
example/triangle_ta_fullscreen.elf: $(START_OBJ) $(TRIANGLE_TA_FULLSCREEN_OBJ)

264
dreamcast2/example/triangle_ta_fullscreen.cpp Normal file
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@ -0,0 +1,264 @@
#include "memorymap.hpp"
#include "holly/core/object_list_bits.hpp"
#include "holly/core/region_array.hpp"
#include "holly/core/region_array_bits.hpp"
#include "holly/core/parameter_bits.hpp"
#include "holly/core/parameter.hpp"
#include "holly/ta/global_parameter.hpp"
#include "holly/ta/vertex_parameter.hpp"
#include "holly/ta/parameter_bits.hpp"
#include "holly/holly.hpp"
#include "holly/holly_bits.hpp"
#include "sh7091/sh7091.hpp"
#include "sh7091/pref.hpp"
void transfer_background_polygon(uint32_t isp_tsp_parameter_start)
{
using namespace holly::core::parameter;
using parameter = isp_tsp_parameter<3>;
volatile parameter * polygon = (volatile parameter *)&texture_memory32[isp_tsp_parameter_start];
polygon->isp_tsp_instruction_word = isp_tsp_instruction_word::depth_compare_mode::always
| isp_tsp_instruction_word::culling_mode::no_culling;
polygon->tsp_instruction_word = tsp_instruction_word::src_alpha_instr::one
| tsp_instruction_word::dst_alpha_instr::zero
| tsp_instruction_word::fog_control::no_fog;
polygon->texture_control_word = 0;
polygon->vertex[0].x = 0.0f;
polygon->vertex[0].y = 0.0f;
polygon->vertex[0].z = 0.00001f;
polygon->vertex[0].base_color = 0xff00ff;
polygon->vertex[1].x = 32.0f;
polygon->vertex[1].y = 0.0f;
polygon->vertex[1].z = 0.00001f;
polygon->vertex[1].base_color = 0xff00ff;
polygon->vertex[2].x = 32.0f;
polygon->vertex[2].y = 32.0f;
polygon->vertex[2].z = 0.00001f;
polygon->vertex[2].base_color = 0xff00ff;
}
void transfer_ta_triangle()
{
using namespace sh7091;
using sh7091::sh7091;
sh7091.CCN.QACR0 = sh7091::ccn::qacr0::address(ta_fifo_polygon_converter);
sh7091.CCN.QACR1 = sh7091::ccn::qacr1::address(ta_fifo_polygon_converter);
uint32_t store_queue_ix = 0;
using namespace holly::core::parameter;
using namespace holly::ta;
using namespace holly::ta::parameter;
//
// TA polygon global transfer
//
volatile global_parameter::polygon_type_0 * polygon = (volatile global_parameter::polygon_type_0 *)&store_queue[store_queue_ix];
store_queue_ix += (sizeof (global_parameter::polygon_type_0));
polygon->parameter_control_word = parameter_control_word::para_type::polygon_or_modifier_volume
| parameter_control_word::list_type::opaque
| parameter_control_word::col_type::packed_color
| parameter_control_word::gouraud;
polygon->isp_tsp_instruction_word = isp_tsp_instruction_word::depth_compare_mode::always
| isp_tsp_instruction_word::culling_mode::no_culling;
polygon->tsp_instruction_word = tsp_instruction_word::src_alpha_instr::one
| tsp_instruction_word::dst_alpha_instr::zero
| tsp_instruction_word::fog_control::no_fog;
pref(polygon);
//
// TA polygon vertex transfer
//
volatile vertex_parameter::polygon_type_0 * vertex = (volatile vertex_parameter::polygon_type_0 *)&store_queue[store_queue_ix];
store_queue_ix += (sizeof (vertex_parameter::polygon_type_0)) * 3;
// bottom left
vertex[0].parameter_control_word = parameter_control_word::para_type::vertex_parameter;
vertex[0].x = 77.0f;
vertex[0].y = 450.0f;
vertex[0].z = 0.1f;
vertex[0].base_color = 0xff0000; // red
// start store queue transfer of `vertex[0]` to the TA
pref(&vertex[0]);
// top center
vertex[1].parameter_control_word = parameter_control_word::para_type::vertex_parameter;
vertex[1].x = 320.0f;
vertex[1].y = 30.0f;
vertex[1].z = 0.1f;
vertex[1].base_color = 0x00ff00; // green
// start store queue transfer of `vertex[1]` to the TA
pref(&vertex[1]);
// bottom right
vertex[2].parameter_control_word = parameter_control_word::para_type::vertex_parameter
| parameter_control_word::end_of_strip;
vertex[2].x = 562.0f;
vertex[2].y = 450.0f;
vertex[2].z = 0.1f;
vertex[2].base_color = 0x0000ff; // blue
// start store queue transfer of `params[2]` to the TA
pref(&vertex[2]);
//
// TA "end of list" global transfer
//
volatile global_parameter::end_of_list * end_of_list = (volatile global_parameter::end_of_list *)&store_queue[store_queue_ix];
store_queue_ix += (sizeof (global_parameter::end_of_list));
end_of_list->parameter_control_word = parameter_control_word::para_type::end_of_list;
// start store queue transfer of `end_of_list` to the TA
pref(end_of_list);
}
void main()
{
/*
a very simple memory map:
the ordering within texture memory is not significant, and could be
anything
*/
uint32_t framebuffer_start = 0x200000; // intentionally the same address that the boot rom used to draw the SEGA logo
uint32_t isp_tsp_parameter_start = 0x400000;
uint32_t region_array_start = 0x500000;
uint32_t object_list_start = 0x100000;
const int tile_y_num = 480 / 32;
const int tile_x_num = 640 / 32;
using namespace holly::core;
region_array::list_block_size list_block_size = {
.opaque = 8 * 4,
};
region_array::transfer(tile_x_num,
tile_y_num,
list_block_size,
region_array_start,
object_list_start);
transfer_background_polygon(isp_tsp_parameter_start);
//////////////////////////////////////////////////////////////////////////////
// configure the TA
//////////////////////////////////////////////////////////////////////////////
using namespace holly;
using holly::holly;
// TA_GLOB_TILE_CLIP restricts which "object pointer blocks" are written
// to.
//
// This can also be used to implement "windowing", as long as the desired
// window size happens to be a multiple of 32 pixels. The "User Tile Clip" TA
// control parameter can also ~equivalently be used as many times as desired
// within a single TA initialization to produce an identical effect.
//
// See DCDBSysArc990907E.pdf page 183.
holly.TA_GLOB_TILE_CLIP = ta_glob_tile_clip::tile_y_num(tile_y_num - 1)
| ta_glob_tile_clip::tile_x_num(tile_x_num - 1);
// While CORE supports arbitrary-length object lists, the TA uses "object
// pointer blocks" as a memory allocation strategy. These fixed-length blocks
// can still have infinite length via "object pointer block links". This
// mechanism is illustrated in DCDBSysArc990907E.pdf page 188.
holly.TA_ALLOC_CTRL = ta_alloc_ctrl::opb_mode::increasing_addresses
| ta_alloc_ctrl::o_opb::_8x4byte;
// While building object lists, the TA contains an internal index (exposed as
// the read-only TA_ITP_CURRENT) for the next address that new ISP/TSP will be
// stored at. The initial value of this index is TA_ISP_BASE.
// reserve space in ISP/TSP parameters for the background parameter
using polygon = holly::core::parameter::isp_tsp_parameter<3>;
uint32_t ta_isp_base_offset = (sizeof (polygon)) * 1;
holly.TA_ISP_BASE = isp_tsp_parameter_start + ta_isp_base_offset;
holly.TA_ISP_LIMIT = isp_tsp_parameter_start + 0x100000;
// Similarly, the TA also contains, for up to 600 tiles, an internal index for
// the next address that an object list entry will be stored for each
// tile. These internal indicies are partially exposed via the read-only
// TA_OL_POINTERS.
holly.TA_OL_BASE = object_list_start;
// TA_OL_LIMIT, DCDBSysArc990907E.pdf page 385:
//
// > Because the TA may automatically store data in the address that is
// > specified by this register, it must not be used for other data. For
// > example, the address specified here must not be the same as the address
// > in the TA_ISP_BASE register.
holly.TA_OL_LIMIT = object_list_start + 0x100000 - 32;
holly.TA_LIST_INIT = ta_list_init::list_init;
// dummy TA_LIST_INIT read; DCDBSysArc990907E.pdf in multiple places says this
// step is required.
(void)holly.TA_LIST_INIT;
//////////////////////////////////////////////////////////////////////////////
// transfer triangles to texture memory via the TA polygon converter FIFO
//////////////////////////////////////////////////////////////////////////////
transfer_ta_triangle();
//////////////////////////////////////////////////////////////////////////////
// configure CORE
//////////////////////////////////////////////////////////////////////////////
// REGION_BASE is the (texture memory-relative) address of the region array.
holly.REGION_BASE = region_array_start;
// PARAM_BASE is the (texture memory-relative) address of ISP/TSP parameters.
// Anything that references an ISP/TSP parameter does so relative to this
// address (and not relative to the beginning of texture memory).
holly.PARAM_BASE = isp_tsp_parameter_start;
// Set the offset of the background ISP/TSP parameter, relative to PARAM_BASE
// SKIP is related to the size of each vertex
uint32_t background_offset = 0;
holly.ISP_BACKGND_T = isp_backgnd_t::tag_address(background_offset / 4)
| isp_backgnd_t::tag_offset(0)
| isp_backgnd_t::skip(1);
// FB_W_SOF1 is the (texture memory-relative) address of the framebuffer that
// will be written to when a tile is rendered/flushed.
holly.FB_W_SOF1 = framebuffer_start;
// start the actual render--the rendering process begins by interpreting the
// region array
holly.STARTRENDER = 1;
// without waiting for rendering to actually complete, immediately display the
// framebuffer.
holly.FB_R_SOF1 = framebuffer_start;
// return from main; this will effectively jump back to the serial loader
while (1);
}