summaryrefslogtreecommitdiffstatshomepage
path: root/src/mame/video/scotrsht.cpp
blob: 5a610761b258882745fdf17bd0f5280789955313 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
// license:BSD-3-Clause
// copyright-holders:David Haywood, Pierpaolo Prazzoli
#include "emu.h"
#include "includes/scotrsht.h"


/* Similar as Iron Horse */
PALETTE_INIT_MEMBER(scotrsht_state, scotrsht)
{
	const uint8_t *color_prom = memregion("proms")->base();
	int i;

	/* create a lookup table for the palette */
	for (i = 0; i < 0x100; i++)
	{
		int r = pal4bit(color_prom[i + 0x000]);
		int g = pal4bit(color_prom[i + 0x100]);
		int b = pal4bit(color_prom[i + 0x200]);

		palette.set_indirect_color(i, rgb_t(r, g, b));
	}

	/* color_prom now points to the beginning of the lookup table */
	color_prom += 0x300;

	/* characters use colors 0x80-0xff, sprites use colors 0-0x7f */
	for (i = 0; i < 0x200; i++)
	{
		int j;

		for (j = 0; j < 8; j++)
		{
			uint8_t ctabentry = ((~i & 0x100) >> 1) | (j << 4) | (color_prom[i] & 0x0f);
			palette.set_pen_indirect(((i & 0x100) << 3) | (j << 8) | (i & 0xff), ctabentry);
		}
	}
}

WRITE8_MEMBER(scotrsht_state::videoram_w)
{
	m_videoram[offset] = data;
	m_bg_tilemap->mark_tile_dirty(offset);
}

WRITE8_MEMBER(scotrsht_state::colorram_w)
{
	m_colorram[offset] = data;
	m_bg_tilemap->mark_tile_dirty(offset);
}

WRITE8_MEMBER(scotrsht_state::charbank_w)
{
	if (m_charbank != (data & 0x01))
	{
		m_charbank = data & 0x01;
		m_bg_tilemap->mark_all_dirty();
	}

	/* other bits unknown */
}

WRITE8_MEMBER(scotrsht_state::palettebank_w)
{
	if (m_palette_bank != ((data & 0x70) >> 4))
	{
		m_palette_bank = ((data & 0x70) >> 4);
		m_bg_tilemap->mark_all_dirty();
	}

	machine().bookkeeping().coin_counter_w(0, data & 1);
	machine().bookkeeping().coin_counter_w(1, data & 2);

	// data & 4 unknown
}


TILE_GET_INFO_MEMBER(scotrsht_state::get_bg_tile_info)
{
	int attr = m_colorram[tile_index];
	int code = m_videoram[tile_index] + (m_charbank << 9) + ((attr & 0x40) << 2);
	int color = (attr & 0x0f) + m_palette_bank * 16;
	int flag = 0;

	if(attr & 0x10) flag |= TILE_FLIPX;
	if(attr & 0x20) flag |= TILE_FLIPY;

	// data & 0x80 -> tile priority?

	SET_TILE_INFO_MEMBER(0, code, color, flag);
}

/* Same as Jailbreak + palette bank */
void scotrsht_state::draw_sprites(bitmap_ind16 &bitmap, const rectangle &cliprect )
{
	for (int i = 0; i < m_spriteram.bytes(); i += 4)
	{
		int attr = m_spriteram[i + 1];    // attributes = ?tyxcccc
		int code = m_spriteram[i] + ((attr & 0x40) << 2);
		int color = (attr & 0x0f) + m_palette_bank * 16;
		int flipx = attr & 0x10;
		int flipy = attr & 0x20;
		int sx = m_spriteram[i + 2] - ((attr & 0x80) << 1);
		int sy = m_spriteram[i + 3];

		if (flip_screen())
		{
			sx = 240 - sx;
			sy = 240 - sy;
			flipx = !flipx;
			flipy = !flipy;
		}

		m_gfxdecode->gfx(1)->transmask(bitmap,cliprect, code, color, flipx, flipy,
			sx, sy,
			m_palette->transpen_mask(*m_gfxdecode->gfx(1), color, m_palette_bank * 16));
	}
}

void scotrsht_state::video_start()
{
	m_bg_tilemap = &machine().tilemap().create(*m_gfxdecode, tilemap_get_info_delegate(FUNC(scotrsht_state::get_bg_tile_info),this), TILEMAP_SCAN_ROWS,  8, 8, 64, 32);

	m_bg_tilemap->set_scroll_cols(64);

	save_item(NAME(m_irq_enable));
	save_item(NAME(m_charbank));
	save_item(NAME(m_palette_bank));
}

uint32_t scotrsht_state::screen_update(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect)
{
	for (int col = 0; col < 32; col++)
		m_bg_tilemap->set_scrolly(col, m_scroll[col]);

	m_bg_tilemap->draw(screen, bitmap, cliprect, 0, 0);
	draw_sprites(bitmap, cliprect);
	return 0;
}