src/include/video.h

/*
 *  video.h - Video/graphics emulation
 *
 *  Basilisk II (C) 1997-2001 Christian Bauer
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#ifndef VIDEO_H
#define VIDEO_H

#include <vector>

#ifndef NO_STD_NAMESPACE
using std::vector;
#endif

/*
   Some of the terminology here is completely frelled. In Basilisk II, a
   "video mode" refers to a combination of resolution and color depth, and
   this information is stored in a video_mode structure. In Apple
   documentation, a "mode" historically refers to the color depth only
   (because old Macs had fixed-frequency monitors and could not change the
   resolution). These "modes" are assigned a number (0x80, 0x81, etc.),
   which we here call "Apple mode". When Macs learned how to deal with
   multiscan monitors, Apple introduced another type of "mode", also having
   numbers starting from 0x80 but refrerring to the resolution and/or video
   timing of the display (it's possible to have two modes with the same
   dimension but different refresh rates). We call this a "resolution ID". 
   The combination of "Apple mode" and "ID" corresponds to a Basilisk II
   "video mode". To make the confusion worse, the video driver control call
   that sets the color depth is called "SetMode" while the one that sets
   both depth and resolution is "SwitchMode"...
*/

// Color depth codes
enum video_depth {
        VDEPTH_1BIT,  // 2 colors
        VDEPTH_2BIT,  // 4 colors
        VDEPTH_4BIT,  // 16 colors
        VDEPTH_8BIT,  // 256 colors
        VDEPTH_16BIT, // "Thousands"
        VDEPTH_32BIT  // "Millions"
};

inline uint16 DepthToAppleMode(video_depth depth)
{
        return depth + 0x80;
}

inline video_depth AppleModeToDepth(uint16 mode)
{
        return video_depth(mode - 0x80);
}

inline bool IsDirectMode(video_depth depth)
{
        return depth == VDEPTH_16BIT || depth == VDEPTH_32BIT;
}

inline bool IsDirectMode(uint16 mode)
{
        return IsDirectMode(AppleModeToDepth(mode));
}

// Return the depth code that corresponds to the specified bits-per-pixel value
inline video_depth DepthModeForPixelDepth(int depth)
{
        switch (depth) {
                case 1: return VDEPTH_1BIT;
                case 2: return VDEPTH_2BIT;
                case 4: return VDEPTH_4BIT;
                case 8: return VDEPTH_8BIT;
                case 15: case 16: return VDEPTH_16BIT;
                case 24: case 32: return VDEPTH_32BIT;
                default: return VDEPTH_1BIT;
        }
}

// Return a bytes-per-row value (assuming no padding) for the specified depth and pixel width
inline uint32 TrivialBytesPerRow(uint32 width, video_depth depth)
{
        switch (depth) {
                case VDEPTH_1BIT: return width / 8;
                case VDEPTH_2BIT: return width / 4;
                case VDEPTH_4BIT: return width / 2;
                case VDEPTH_8BIT: return width;
                case VDEPTH_16BIT: return width * 2;
                case VDEPTH_32BIT: return width * 4;
                default: return width;
        }
}

/*
   You are not completely free in your selection of depth/resolution
   combinations:
     1) the lowest supported color depth must be available in all
        resolutions
     2) if one resolution provides a certain color depth, it must also
        provide all lower supported depths

   For example, it is possible to have this set of modes:
     640x480 @ 8 bit
     640x480 @ 32 bit
     800x600 @ 8 bit
     800x600 @ 32 bit
     1024x768 @ 8 bit

   But this is not possible (violates rule 1):
     640x480 @ 8 bit
     800x600 @ 8 bit
     1024x768 @ 1 bit

   And neither is this (violates rule 2, 640x480 @ 16 bit is missing):
     640x480 @ 8 bit
     640x480 @ 32 bit
     800x600 @ 8 bit
     800x600 @ 16 bit
     1024x768 @ 8 bit
*/

// Description of a video mode
struct video_mode {
        uint32 x;                               // X size of screen (pixels)
        uint32 y;                               // Y size of screen (pixels)
        uint32 resolution_id;   // Resolution ID (should be >= 0x80 and uniquely identify the sets of modes with the same X/Y size)
        uint32 bytes_per_row;   // Bytes per row of frame buffer
        video_depth depth;              // Color depth (see definitions above)
};

inline bool IsDirectMode(const video_mode &mode)
{
        return IsDirectMode(mode.depth);
}

// List of all supported video modes
extern vector<video_mode> VideoModes;

// Description for one (possibly virtual) monitor
struct monitor_desc {
        uint32 mac_frame_base;  // Mac frame buffer address
        video_mode mode;                // Currently selected video mode description
};

// Description of the main (and currently the only) monitor, set by VideoInit()
extern monitor_desc VideoMonitor;

extern int16 VideoDriverOpen(uint32 pb, uint32 dce);
extern int16 VideoDriverControl(uint32 pb, uint32 dce);
extern int16 VideoDriverStatus(uint32 pb, uint32 dce);

// System specific and internal functions/data
extern bool VideoInit(bool classic);
extern void VideoExit(void);

extern void VideoQuitFullScreen(void);

extern void VideoInterrupt(void);
extern void VideoRefresh(void);

// Called by the video driver to switch the video mode
extern void video_switch_to_mode(const video_mode &mode);

// Called by the video driver to set the color palette (in indexed modes)
// or gamma table (in direct modes)
extern void video_set_palette(uint8 *pal, int num);

#endif
Revision:	1.11
Committed:	2001-07-01T21:09:30Z (23 years, 4 months ago) by cebix
Content type:	text/plain
Branch:	MAIN
Changes since 1.10:	+1 -1 lines
Log Message:	- video_set_palette() gets passed the number of used palette entries - video_x.cpp supports 2- and 4-bit modes on truecolor screens
#	User	Rev	Content
1	cebix	1.1	/*
2			* video.h - Video/graphics emulation
3			*
4	cebix	1.5	* Basilisk II (C) 1997-2001 Christian Bauer
5	cebix	1.1	*
6			* This program is free software; you can redistribute it and/or modify
7			* it under the terms of the GNU General Public License as published by
8			* the Free Software Foundation; either version 2 of the License, or
9			* (at your option) any later version.
10			*
11			* This program is distributed in the hope that it will be useful,
12			* but WITHOUT ANY WARRANTY; without even the implied warranty of
13			* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14			* GNU General Public License for more details.
15			*
16			* You should have received a copy of the GNU General Public License
17			* along with this program; if not, write to the Free Software
18			* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19			*/
20
21			#ifndef VIDEO_H
22			#define VIDEO_H
23
24	cebix	1.6	#include <vector>
25
26	cebix	1.10	#ifndef NO_STD_NAMESPACE
27			using std::vector;
28			#endif
29
30	cebix	1.9	/*
31			Some of the terminology here is completely frelled. In Basilisk II, a
32			"video mode" refers to a combination of resolution and color depth, and
33			this information is stored in a video_mode structure. In Apple
34			documentation, a "mode" historically refers to the color depth only
35			(because old Macs had fixed-frequency monitors and could not change the
36			resolution). These "modes" are assigned a number (0x80, 0x81, etc.),
37			which we here call "Apple mode". When Macs learned how to deal with
38			multiscan monitors, Apple introduced another type of "mode", also having
39			numbers starting from 0x80 but refrerring to the resolution and/or video
40			timing of the display (it's possible to have two modes with the same
41			dimension but different refresh rates). We call this a "resolution ID".
42			The combination of "Apple mode" and "ID" corresponds to a Basilisk II
43			"video mode". To make the confusion worse, the video driver control call
44			that sets the color depth is called "SetMode" while the one that sets
45			both depth and resolution is "SwitchMode"...
46			*/
47
48	cebix	1.6	// Color depth codes
49			enum video_depth {
50			VDEPTH_1BIT, // 2 colors
51			VDEPTH_2BIT, // 4 colors
52			VDEPTH_4BIT, // 16 colors
53			VDEPTH_8BIT, // 256 colors
54			VDEPTH_16BIT, // "Thousands"
55			VDEPTH_32BIT // "Millions"
56	cebix	1.1	};
57
58	cebix	1.8	inline uint16 DepthToAppleMode(video_depth depth)
59			{
60			return depth + 0x80;
61			}
62
63			inline video_depth AppleModeToDepth(uint16 mode)
64			{
65			return video_depth(mode - 0x80);
66			}
67
68	cebix	1.6	inline bool IsDirectMode(video_depth depth)
69			{
70			return depth == VDEPTH_16BIT \|\| depth == VDEPTH_32BIT;
71			}
72
73	cebix	1.8	inline bool IsDirectMode(uint16 mode)
74			{
75			return IsDirectMode(AppleModeToDepth(mode));
76			}
77
78	cebix	1.9	// Return the depth code that corresponds to the specified bits-per-pixel value
79	cebix	1.8	inline video_depth DepthModeForPixelDepth(int depth)
80	cebix	1.6	{
81	cebix	1.8	switch (depth) {
82			case 1: return VDEPTH_1BIT;
83			case 2: return VDEPTH_2BIT;
84			case 4: return VDEPTH_4BIT;
85			case 8: return VDEPTH_8BIT;
86			case 15: case 16: return VDEPTH_16BIT;
87			case 24: case 32: return VDEPTH_32BIT;
88			default: return VDEPTH_1BIT;
89			}
90	cebix	1.6	}
91	cebix	1.1
92	cebix	1.9	// Return a bytes-per-row value (assuming no padding) for the specified depth and pixel width
93	cebix	1.8	inline uint32 TrivialBytesPerRow(uint32 width, video_depth depth)
94	cebix	1.6	{
95	cebix	1.8	switch (depth) {
96			case VDEPTH_1BIT: return width / 8;
97			case VDEPTH_2BIT: return width / 4;
98			case VDEPTH_4BIT: return width / 2;
99			case VDEPTH_8BIT: return width;
100			case VDEPTH_16BIT: return width * 2;
101			case VDEPTH_32BIT: return width * 4;
102	cebix	1.10	default: return width;
103	cebix	1.8	}
104	cebix	1.6	}
105
106	cebix	1.9	/*
107			You are not completely free in your selection of depth/resolution
108			combinations:
109			1) the lowest supported color depth must be available in all
110			resolutions
111			2) if one resolution provides a certain color depth, it must also
112			provide all lower supported depths
113
114			For example, it is possible to have this set of modes:
115			640x480 @ 8 bit
116			640x480 @ 32 bit
117			800x600 @ 8 bit
118			800x600 @ 32 bit
119			1024x768 @ 8 bit
120
121			But this is not possible (violates rule 1):
122			640x480 @ 8 bit
123			800x600 @ 8 bit
124			1024x768 @ 1 bit
125
126			And neither is this (violates rule 2, 640x480 @ 16 bit is missing):
127			640x480 @ 8 bit
128			640x480 @ 32 bit
129			800x600 @ 8 bit
130			800x600 @ 16 bit
131			1024x768 @ 8 bit
132			*/
133
134			// Description of a video mode
135	cebix	1.6	struct video_mode {
136	cebix	1.1	uint32 x; // X size of screen (pixels)
137			uint32 y; // Y size of screen (pixels)
138	cebix	1.6	uint32 resolution_id; // Resolution ID (should be >= 0x80 and uniquely identify the sets of modes with the same X/Y size)
139			uint32 bytes_per_row; // Bytes per row of frame buffer
140			video_depth depth; // Color depth (see definitions above)
141			};
142
143			inline bool IsDirectMode(const video_mode &mode)
144			{
145			return IsDirectMode(mode.depth);
146			}
147
148			// List of all supported video modes
149	cebix	1.10	extern vector<video_mode> VideoModes;
150	cebix	1.6
151			// Description for one (possibly virtual) monitor
152			struct monitor_desc {
153			uint32 mac_frame_base; // Mac frame buffer address
154			video_mode mode; // Currently selected video mode description
155	cebix	1.1	};
156
157	cebix	1.9	// Description of the main (and currently the only) monitor, set by VideoInit()
158			extern monitor_desc VideoMonitor;
159	cebix	1.1
160	cebix	1.2	extern int16 VideoDriverOpen(uint32 pb, uint32 dce);
161			extern int16 VideoDriverControl(uint32 pb, uint32 dce);
162			extern int16 VideoDriverStatus(uint32 pb, uint32 dce);
163	cebix	1.1
164			// System specific and internal functions/data
165			extern bool VideoInit(bool classic);
166			extern void VideoExit(void);
167
168			extern void VideoQuitFullScreen(void);
169
170			extern void VideoInterrupt(void);
171	cebix	1.4	extern void VideoRefresh(void);
172	cebix	1.1
173	cebix	1.9	// Called by the video driver to switch the video mode
174	cebix	1.7	extern void video_switch_to_mode(const video_mode &mode);
175	cebix	1.9
176			// Called by the video driver to set the color palette (in indexed modes)
177			// or gamma table (in direct modes)
178	cebix	1.11	extern void video_set_palette(uint8 *pal, int num);
179	cebix	1.1
180			#endif