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/* |
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* video.h - Video/graphics emulation |
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* |
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* Basilisk II (C) 1997-2001 Christian Bauer |
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* |
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* This program is free software; you can redistribute it and/or modify |
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* it under the terms of the GNU General Public License as published by |
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* the Free Software Foundation; either version 2 of the License, or |
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* (at your option) any later version. |
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* |
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* This program is distributed in the hope that it will be useful, |
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* but WITHOUT ANY WARRANTY; without even the implied warranty of |
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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* GNU General Public License for more details. |
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* |
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* You should have received a copy of the GNU General Public License |
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* along with this program; if not, write to the Free Software |
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
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*/ |
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|
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#ifndef VIDEO_H |
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#define VIDEO_H |
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|
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#include <vector> |
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|
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#ifndef NO_STD_NAMESPACE |
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using std::vector; |
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#endif |
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|
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/* |
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Some of the terminology here is completely frelled. In Basilisk II, a |
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"video mode" refers to a combination of resolution and color depth, and |
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this information is stored in a video_mode structure. In Apple |
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documentation, a "mode" historically refers to the color depth only |
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(because old Macs had fixed-frequency monitors and could not change the |
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resolution). These "modes" are assigned a number (0x80, 0x81, etc.), |
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which we here call "Apple mode". When Macs learned how to deal with |
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multiscan monitors, Apple introduced another type of "mode", also having |
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numbers starting from 0x80 but refrerring to the resolution and/or video |
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timing of the display (it's possible to have two modes with the same |
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dimension but different refresh rates). We call this a "resolution ID". |
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The combination of "Apple mode" and "ID" corresponds to a Basilisk II |
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"video mode". To make the confusion worse, the video driver control call |
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that sets the color depth is called "SetMode" while the one that sets |
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both depth and resolution is "SwitchMode"... |
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*/ |
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|
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// Color depth codes |
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enum video_depth { |
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VDEPTH_1BIT, // 2 colors |
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VDEPTH_2BIT, // 4 colors |
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VDEPTH_4BIT, // 16 colors |
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VDEPTH_8BIT, // 256 colors |
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VDEPTH_16BIT, // "Thousands" |
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VDEPTH_32BIT // "Millions" |
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}; |
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|
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inline uint16 DepthToAppleMode(video_depth depth) |
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{ |
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return depth + 0x80; |
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} |
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|
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inline video_depth AppleModeToDepth(uint16 mode) |
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{ |
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return video_depth(mode - 0x80); |
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} |
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|
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inline bool IsDirectMode(video_depth depth) |
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{ |
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return depth == VDEPTH_16BIT || depth == VDEPTH_32BIT; |
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} |
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|
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inline bool IsDirectMode(uint16 mode) |
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{ |
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return IsDirectMode(AppleModeToDepth(mode)); |
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} |
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|
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// Return the depth code that corresponds to the specified bits-per-pixel value |
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inline video_depth DepthModeForPixelDepth(int depth) |
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{ |
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switch (depth) { |
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case 1: return VDEPTH_1BIT; |
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case 2: return VDEPTH_2BIT; |
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case 4: return VDEPTH_4BIT; |
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case 8: return VDEPTH_8BIT; |
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case 15: case 16: return VDEPTH_16BIT; |
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case 24: case 32: return VDEPTH_32BIT; |
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default: return VDEPTH_1BIT; |
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} |
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} |
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|
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// Return a bytes-per-row value (assuming no padding) for the specified depth and pixel width |
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inline uint32 TrivialBytesPerRow(uint32 width, video_depth depth) |
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{ |
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switch (depth) { |
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case VDEPTH_1BIT: return width / 8; |
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case VDEPTH_2BIT: return width / 4; |
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case VDEPTH_4BIT: return width / 2; |
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case VDEPTH_8BIT: return width; |
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case VDEPTH_16BIT: return width * 2; |
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case VDEPTH_32BIT: return width * 4; |
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default: return width; |
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} |
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} |
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|
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/* |
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You are not completely free in your selection of depth/resolution |
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combinations: |
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1) the lowest supported color depth must be available in all |
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resolutions |
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2) if one resolution provides a certain color depth, it must also |
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provide all lower supported depths |
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|
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For example, it is possible to have this set of modes: |
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640x480 @ 8 bit |
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640x480 @ 32 bit |
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800x600 @ 8 bit |
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800x600 @ 32 bit |
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1024x768 @ 8 bit |
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|
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But this is not possible (violates rule 1): |
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640x480 @ 8 bit |
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800x600 @ 8 bit |
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1024x768 @ 1 bit |
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|
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And neither is this (violates rule 2, 640x480 @ 16 bit is missing): |
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640x480 @ 8 bit |
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640x480 @ 32 bit |
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800x600 @ 8 bit |
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800x600 @ 16 bit |
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1024x768 @ 8 bit |
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*/ |
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|
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// Description of a video mode |
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struct video_mode { |
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uint32 x; // X size of screen (pixels) |
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uint32 y; // Y size of screen (pixels) |
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uint32 resolution_id; // Resolution ID (should be >= 0x80 and uniquely identify the sets of modes with the same X/Y size) |
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uint32 bytes_per_row; // Bytes per row of frame buffer |
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video_depth depth; // Color depth (see definitions above) |
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}; |
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|
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inline bool IsDirectMode(const video_mode &mode) |
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{ |
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return IsDirectMode(mode.depth); |
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} |
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|
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// List of all supported video modes |
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extern vector<video_mode> VideoModes; |
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|
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// Description for one (possibly virtual) monitor |
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struct monitor_desc { |
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uint32 mac_frame_base; // Mac frame buffer address |
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video_mode mode; // Currently selected video mode description |
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}; |
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|
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// Description of the main (and currently the only) monitor, set by VideoInit() |
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extern monitor_desc VideoMonitor; |
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|
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extern int16 VideoDriverOpen(uint32 pb, uint32 dce); |
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extern int16 VideoDriverControl(uint32 pb, uint32 dce); |
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extern int16 VideoDriverStatus(uint32 pb, uint32 dce); |
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|
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// System specific and internal functions/data |
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extern bool VideoInit(bool classic); |
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extern void VideoExit(void); |
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|
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extern void VideoQuitFullScreen(void); |
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|
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extern void VideoInterrupt(void); |
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extern void VideoRefresh(void); |
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|
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// Called by the video driver to switch the video mode |
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extern void video_switch_to_mode(const video_mode &mode); |
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|
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// Called by the video driver to set the color palette (in indexed modes) |
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// or gamma table (in direct modes) |
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extern void video_set_palette(uint8 *pal); |
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|
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#endif |
