ReC98/th03/main/playfld.cpp

#include "platform.h"
#include "pc98.h"
#include "th03/main/playfld.hpp"

playfield_subpixel_t pascal screen_x_to_playfield(screen_x_t x, pid2 pid)
{
	_BX = _SP; // ZUN bloat: Has no effect.

	// ZUN bloat: Abuses the assertion.
	screen_x_t playfield_left = pid;
	static_assert(PLAYFIELD1_CLIP_LEFT == 0);
	if(static_cast<int8_t>(playfield_left)) { // ZUN bloat: Needless 8-bit cast
		playfield_left = PLAYFIELD_W_BORDERED;
	}
	return TO_SP(((x - playfield_left) - PLAYFIELD_BORDER));
}

bool pascal playfield_clip(
	PlayfieldSubpixel center_x, PlayfieldSubpixel center_y
)
{
	// ZUN bloat: Needlessly micro-optimized.
	_AX = false;
	playfield_subpixel_t y;
	playfield_subpixel_t x = center_x;
	y = center_y;

	_BX = playfield_clip_negative_radius.x;
	if(x <= static_cast<playfield_subpixel_t>(_BX)) {
		goto outside;
	}
	asm { neg bx };
	_BX += to_sp(PLAYFIELD_W);
	if(x >= static_cast<playfield_subpixel_t>(_BX)) {
		goto outside;
	}

	_BX = playfield_clip_negative_radius.y;
	if(y <= static_cast<playfield_subpixel_t>(_BX)) {
		goto outside;
	}
	asm { neg bx };
	_BX += to_sp(PLAYFIELD_H);
	if(y < static_cast<playfield_subpixel_t>(_BX)) {
		goto inside;
	}
outside:
	_AL = true;
inside:
	return _AX;
}

#pragma codestring "\x90"