1 // license:BSD-3-Clause
2 // copyright-holders:Aaron Giles, Phil Bennett
3 /***************************************************************************
4
5 Atari Cyberstorm hardware
6
7 ****************************************************************************/
8
9 #include "emu.h"
10 #include "includes/cybstorm.h"
11
12
13
14 /*************************************
15 *
16 * Tilemap callbacks
17 *
18 *************************************/
19
TILE_GET_INFO_MEMBER(cybstorm_state::get_alpha_tile_info)20 TILE_GET_INFO_MEMBER(cybstorm_state::get_alpha_tile_info)
21 {
22 uint16_t data = m_vad->alpha().basemem_read(tile_index);
23 int code = ((data & 0x400) ? (m_alpha_tile_bank * 0x400) : 0) + (data & 0x3ff);
24 int color = (data >> 11) & 0x0f;
25 int opaque = data & 0x8000;
26 tileinfo.set(2, code, color, opaque ? TILEMAP_PIXEL_LAYER0 : 0);
27 }
28
29
TILE_GET_INFO_MEMBER(cybstorm_state::get_playfield_tile_info)30 TILE_GET_INFO_MEMBER(cybstorm_state::get_playfield_tile_info)
31 {
32 uint16_t data1 = m_vad->playfield().basemem_read(tile_index);
33 uint16_t data2 = m_vad->playfield().extmem_read(tile_index) & 0xff;
34 int code = data1;
35 int color = 8 + (data2 & 0x07);
36 tileinfo.set(0, code, color, data2 & 0x80 ? TILE_FLIPX : 0);
37 tileinfo.category = (data2 >> 4) & 3;
38 }
39
40
TILE_GET_INFO_MEMBER(cybstorm_state::get_playfield2_tile_info)41 TILE_GET_INFO_MEMBER(cybstorm_state::get_playfield2_tile_info)
42 {
43 uint16_t data1 = m_vad->playfield2().basemem_read(tile_index);
44 uint16_t data2 = m_vad->playfield2().extmem_read(tile_index) >> 8;
45 int code = data1;
46 int color = data2 & 0x07;
47 tileinfo.set(0, code, color, data2 & 0x80 ? TILE_FLIPX : 0);
48 tileinfo.category = (data2 >> 4) & 3;
49 }
50
TILEMAP_MAPPER_MEMBER(cybstorm_state::playfield_scan)51 TILEMAP_MAPPER_MEMBER(cybstorm_state::playfield_scan)
52 {
53 int bank = 1 - (col / (num_cols / 2));
54 return bank * (num_rows * num_cols / 2) + row * (num_cols / 2) + (col % (num_cols / 2));
55 }
56
57
58
59 /*************************************
60 *
61 * Video system start
62 *
63 *************************************/
64
65 const atari_motion_objects_config cybstorm_state::s_mob_config =
66 {
67 1, /* index to which gfx system */
68 1, /* number of motion object banks */
69 1, /* are the entries linked? */
70 0, /* are the entries split? */
71 1, /* render in reverse order? */
72 0, /* render in swapped X/Y order? */
73 0, /* does the neighbor bit affect the next object? */
74 8, /* pixels per SLIP entry (0 for no-slip) */
75 0, /* pixel offset for SLIPs */
76 0, /* maximum number of links to visit/scanline (0=all) */
77
78 0x1000, /* base palette entry */
79 0x1000, /* maximum number of colors */
80 0, /* transparent pen index */
81
82 {{ 0x03ff,0,0,0 }}, /* mask for the link */
83 {{ 0,0x7fff,0,0 }, { 0x3c00,0,0,0 }}, /* mask for the code index */
84 {{ 0,0,0x000f,0 }}, /* mask for the color */
85 {{ 0,0,0xff80,0 }}, /* mask for the X position */
86 {{ 0,0,0,0xff80 }}, /* mask for the Y position */
87 {{ 0,0,0,0x0070 }}, /* mask for the width, in tiles*/
88 {{ 0,0,0,0x0007 }}, /* mask for the height, in tiles */
89 {{ 0,0x8000,0,0 }}, /* mask for the horizontal flip */
90 {{ 0 }}, /* mask for the vertical flip */
91 {{ 0,0,0x0070,0 }}, /* mask for the priority */
92 {{ 0 }}, /* mask for the neighbor */
93 {{ 0 }}, /* mask for absolute coordinates */
94
95 {{ 0 }}, /* mask for the special value */
96 0, /* resulting value to indicate "special" */
97 };
98
video_start()99 void cybstorm_state::video_start()
100 {
101 /* motion objects have 256 color granularity */
102 m_gfxdecode->gfx(1)->set_granularity(256);
103 }
104
105
106
107 /*************************************
108 *
109 * Main refresh
110 *
111 *************************************/
112
screen_update_cybstorm(screen_device & screen,bitmap_ind16 & bitmap,const rectangle & cliprect)113 uint32_t cybstorm_state::screen_update_cybstorm(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect)
114 {
115 m_vad->mob().draw_async(cliprect);
116
117 /* draw the playfield */
118 bitmap_ind8 &priority_bitmap = screen.priority();
119 priority_bitmap.fill(0, cliprect);
120 m_vad->playfield().draw(screen, bitmap, cliprect, 0, 0x00);
121 m_vad->playfield().draw(screen, bitmap, cliprect, 1, 0x01);
122 m_vad->playfield().draw(screen, bitmap, cliprect, 2, 0x02);
123 m_vad->playfield().draw(screen, bitmap, cliprect, 3, 0x03);
124 m_vad->playfield2().draw(screen, bitmap, cliprect, 0, 0x80);
125 m_vad->playfield2().draw(screen, bitmap, cliprect, 1, 0x84);
126 m_vad->playfield2().draw(screen, bitmap, cliprect, 2, 0x88);
127 m_vad->playfield2().draw(screen, bitmap, cliprect, 3, 0x8c);
128
129 /* draw and merge the MO */
130 bitmap_ind16 &mobitmap = m_vad->mob().bitmap();
131 for (const sparse_dirty_rect *rect = m_vad->mob().first_dirty_rect(cliprect); rect != nullptr; rect = rect->next())
132 for (int y = rect->top(); y <= rect->bottom(); y++)
133 {
134 uint16_t const *const mo = &mobitmap.pix(y);
135 uint16_t *const pf = &bitmap.pix(y);
136 uint8_t const *const pri = &priority_bitmap.pix(y);
137 for (int x = rect->left(); x <= rect->right(); x++)
138 if (mo[x])
139 {
140 int const mopriority = mo[x] >> atari_motion_objects_device::PRIORITY_SHIFT;
141
142 /* upper bit of MO priority signals special rendering and doesn't draw anything */
143 if (mopriority & 4)
144 {
145 if ((mopriority & 0x3) != 0)
146 continue;
147 }
148
149 /* foreground playfield case */
150 if (pri[x] & 0x80)
151 {
152 int const pfpriority = (pri[x] >> 2) & 3;
153
154 if (mopriority > pfpriority)
155 pf[x] = (mo[x] & atari_motion_objects_device::DATA_MASK) | 0x1000;
156 }
157
158 /* background playfield case */
159 else
160 {
161 int const pfpriority = pri[x] & 3;
162
163 /* playfield priority 3 always wins */
164 if (pfpriority == 3)
165 ;
166
167 /* otherwise, MOs get shown */
168 else
169 pf[x] = (mo[x] & atari_motion_objects_device::DATA_MASK) | 0x1000;
170 }
171
172 /* don't erase yet -- we need to make another pass later */
173 }
174 }
175
176 /* now go back and process the upper bit of MO priority */
177 for (const sparse_dirty_rect *rect = m_vad->mob().first_dirty_rect(cliprect); rect != nullptr; rect = rect->next())
178 for (int y = rect->top(); y <= rect->bottom(); y++)
179 {
180 uint16_t *const mo = &mobitmap.pix(y);
181 uint16_t *const pf = &bitmap.pix(y);
182 int count = 0;
183 for (int x = rect->left(); x <= rect->right() || (count && x < bitmap.width()); x++)
184 {
185 const uint16_t START_MARKER = ((4 << atari_motion_objects_device::PRIORITY_SHIFT) | 3);
186 const uint16_t END_MARKER = ((4 << atari_motion_objects_device::PRIORITY_SHIFT) | 7);
187 const uint16_t MASK = ((4 << atari_motion_objects_device::PRIORITY_SHIFT) | 0x3f);
188
189 // TODO: Stain pixels should not overlap sprites!
190 if ((mo[x] & MASK) == START_MARKER)
191 {
192 count++;
193 }
194
195 if (count)
196 {
197 // Only applies to PF pixels
198 if ((pf[x] & 0x1000) == 0)
199 {
200 pf[x] |= 0x2000;
201 }
202 }
203
204 if ((mo[x] & MASK) == END_MARKER)
205 {
206 count--;
207 }
208
209 /* erase behind ourselves */
210 mo[x] = 0;
211 }
212 }
213
214 /* add the alpha on top */
215 m_vad->alpha().draw(screen, bitmap, cliprect, 0, 0);
216
217 return 0;
218 }
219