dreamcast/holly/background.cpp

52 lines
1.3 KiB
C++

#include <cstdint>
#include "isp_tsp.hpp"
struct vertex_parameter {
float x;
float y;
float z;
uint32_t base_color;
}; // ISP_BACKGND_T skip(1)
struct isp_tsp_parameter {
uint32_t isp_tsp_instruction_word;
uint32_t tsp_instruction_word;
uint32_t texture_control_word;
vertex_parameter vertex[3];
};
static_assert((sizeof (isp_tsp_parameter)) == (4 * 3 + 3) * 4);
void background_parameter(volatile uint32_t * buf, uint32_t color)
{
volatile isp_tsp_parameter * parameter = reinterpret_cast<volatile isp_tsp_parameter *>(buf);
parameter->isp_tsp_instruction_word
= isp_tsp_instruction_word::depth_compare_mode::always
| isp_tsp_instruction_word::culling_mode::no_culling;
parameter->tsp_instruction_word
= tsp_instruction_word::src_alpha_instr::one
| tsp_instruction_word::dst_alpha_instr::zero
| tsp_instruction_word::fog_control::no_fog;
parameter->texture_control_word
= 0;
parameter->vertex[0].x = 0.f;
parameter->vertex[0].y = 0.f;
parameter->vertex[0].z = 1.f/100000;
parameter->vertex[0].base_color = color;
parameter->vertex[1].x = 639.f;
parameter->vertex[1].y = 0.f;
parameter->vertex[1].z = 1.f/100000;
parameter->vertex[1].base_color = color;
parameter->vertex[2].x = 639.f;
parameter->vertex[2].y = 479.f;
parameter->vertex[2].z = 1.f/100000;
parameter->vertex[2].base_color = color;
}