summaryrefslogtreecommitdiffstatshomepage
path: root/src/mame/video/apple2gs.cpp
blob: 2f10133e7e39623683fb99b5cd31264841fb88b3 (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
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
// license:BSD-3-Clause
// copyright-holders:Nathan Woods,R. Belmont
/*********************************************************************

    video/apple2gs.c

    Apple IIgs video code

*********************************************************************/


#include "emu.h"
#include "includes/apple2.h"
#include "includes/apple2gs.h"



VIDEO_START_MEMBER(apple2gs_state,apple2gs)
{
	m_bordercolor = 0;
	apple2_video_start(m_slowmem.get(), m_slowmem.get()+0x10000, 0, 8);
	m_legacy_gfx = std::make_unique<bitmap_ind16>(560, 192);

	save_item(m_bordercolor, "BORDERCLR");
	save_item(NAME(m_fgcolor));
	save_item(NAME(m_bgcolor));
}



uint32_t apple2gs_state::screen_update_apple2gs(screen_device &screen, bitmap_rgb32 &bitmap, const rectangle &cliprect)
{
	const uint8_t *vram;
	uint32_t *scanline;
	uint8_t scb, b;
	int col, palette;
	uint32_t last_pixel = 0, pixel;
	int beamy;
	uint16_t *a2pixel;

	beamy = cliprect.min_y;

	if (m_newvideo & 0x80)
	{
		// in top or bottom border?
		if ((beamy < BORDER_TOP) || (beamy >= 200+BORDER_TOP))
		{
			// don't draw past the bottom border
			if (beamy >= 231+BORDER_TOP)
			{
				return 0;
			}

			scanline = &bitmap.pix32(beamy);
			for (col = 0; col < BORDER_LEFT+BORDER_RIGHT+640; col++)
			{
				scanline[col] = m_a2_palette[m_bordercolor];
			}
		}
		else    // regular screen area
		{
			int shrline = beamy - BORDER_TOP;

			scb = m_slowmem[0x19D00 + shrline];
			palette = ((scb & 0x0f) << 4);

			vram = &m_slowmem[0x12000 + (shrline * 160)];
			scanline = &bitmap.pix32(beamy);

			// draw left and right borders
			for (col = 0; col < BORDER_LEFT; col++)
			{
				scanline[col] = m_a2_palette[m_bordercolor];
				scanline[col+BORDER_LEFT+640] = m_a2_palette[m_bordercolor];
			}

			if (scb & 0x80) // 640 mode
			{
				for (col = 0; col < 160; col++)
				{
					b = vram[col];
					scanline[col * 4 + 0 + BORDER_LEFT] = m_shr_palette[palette +  0 + ((b >> 6) & 0x03)];
					scanline[col * 4 + 1 + BORDER_LEFT] = m_shr_palette[palette +  4 + ((b >> 4) & 0x03)];
					scanline[col * 4 + 2 + BORDER_LEFT] = m_shr_palette[palette +  8 + ((b >> 2) & 0x03)];
					scanline[col * 4 + 3 + BORDER_LEFT] = m_shr_palette[palette + 12 + ((b >> 0) & 0x03)];
				}
			}
			else        // 320 mode
			{
				for (col = 0; col < 160; col++)
				{
					b = vram[col];
					pixel = (b >> 4) & 0x0f;

					if ((scb & 0x20) && !pixel)
						pixel = last_pixel;
					else
						last_pixel = pixel;
					pixel += palette;
					scanline[col * 4 + 0 + BORDER_LEFT] = m_shr_palette[pixel];
					scanline[col * 4 + 1 + BORDER_LEFT] = m_shr_palette[pixel];

					b = vram[col];
					pixel = (b >> 0) & 0x0f;

					if ((scb & 0x20) && !pixel)
						pixel = last_pixel;
					else
						last_pixel = pixel;
					pixel += palette;
					scanline[col * 4 + 2 + BORDER_LEFT] = m_shr_palette[pixel];
					scanline[col * 4 + 3 + BORDER_LEFT] = m_shr_palette[pixel];
				}
			}
		}
	}
	else
	{
		/* call legacy Apple II video rendering at scanline 0 to draw into the off-screen buffer */
		if (beamy == 0)
		{
			// check if DHR should be monochrome 560x192
			if (m_newvideo & 0x20)
			{
				m_monochrome_dhr = true;
			}
			else
			{
				m_monochrome_dhr = false;
			}

			rectangle new_cliprect(0, 559, 0, 191);
			screen_update_apple2(screen, *m_legacy_gfx, new_cliprect);
		}

		if ((beamy < (BORDER_TOP+4)) || (beamy >= (192+4+BORDER_TOP)))
		{
			if (beamy >= (231+BORDER_TOP))
			{
				return 0;
			}

			scanline = &bitmap.pix32(beamy);
			for (col = 0; col < BORDER_LEFT+BORDER_RIGHT+640; col++)
			{
				scanline[col] = m_a2_palette[m_bordercolor];
			}
		}
		else
		{
			scanline = &bitmap.pix32(beamy);

			// draw left and right borders
			for (col = 0; col < BORDER_LEFT + 40; col++)
			{
				scanline[col] = m_a2_palette[m_bordercolor];
				scanline[col+BORDER_LEFT+600] = m_a2_palette[m_bordercolor];
			}

			a2pixel = &m_legacy_gfx->pix16(beamy-(BORDER_TOP+4));
			for (int x = 0; x < 560; x++)
			{
				scanline[40 + BORDER_LEFT + x] = m_a2_palette[*a2pixel++];
			}
		}
	}
	return 0;
}