freebsd-dev/lib/libvgl/bitmap.c
Bruce Evans 1fa5142093 Use a shadow buffer and never read from the frame buffer. Remove large slow
code for reading from the frame buffer.

Reading from the frame buffer is usually much slower than writing to
the frame buffer.  Typically 10 to 100 times slower.  It old modes,
it takes many more PIOs, and in newer modes with no PIOs writes are
often write-combined while reads remain uncached.

Reading from the frame buffer is not very common, so this change doesn't
give speedups of 10 to 100 times.  My main test case is a floodfill()
function that reads about as many pixels as it writes.  The speedups
are typically a factor of 2 to 4.

Duplicating writes to the shadow buffer is slower when no reads from the
frame buffer are done, but reads are often done for the pixels under the
mouse cursor, and doing these reads from the shadow buffer more than
compensates for the overhead of writing the shadow buffer in at least the
slower modes.  Management of the mouse cursor also becomes simpler.

The shadow buffer doesn't take any extra memory, except twice as much
in old 4-plane modes.  A buffer for holding a copy of the frame buffer
was allocated up front for use in the screen switching signal handler.
This wasn't changed when the handler was made async-signal safe.  Use
the same buffer the shadow (but make it twice as large in the 4-plane
modes), and remove large special code for writing it as well as large
special code for reading ut.  It used to have a rawer format in the
4-plane modes.  Now it has a bitmap format which takes twice as much
memory but can be written almost as fast without special code.

VIDBUFs that are not the whole frame buffer were never supported, and the
change depends on this.  Check for invalid VIDBUFs in some places and do
nothing.  The removed code did something not so good.
2019-04-21 16:17:35 +00:00

277 lines
7.9 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* Copyright (c) 1991-1997 Søren Schmidt
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer,
* in this position and unchanged.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <signal.h>
#include <sys/fbio.h>
#include "vgl.h"
#define min(x, y) (((x) < (y)) ? (x) : (y))
static byte mask[8] = {0xff, 0x7f, 0x3f, 0x1f, 0x0f, 0x07, 0x03, 0x01};
static int color2bit[16] = {0x00000000, 0x00000001, 0x00000100, 0x00000101,
0x00010000, 0x00010001, 0x00010100, 0x00010101,
0x01000000, 0x01000001, 0x01000100, 0x01000101,
0x01010000, 0x01010001, 0x01010100, 0x01010101};
static void
WriteVerticalLine(VGLBitmap *dst, int x, int y, int width, byte *line)
{
int i, pos, last, planepos, start_offset, end_offset, offset;
int len;
unsigned int word = 0;
byte *address;
byte *VGLPlane[4];
switch (dst->Type) {
case VIDBUF4:
case VIDBUF4S:
start_offset = (x & 0x07);
end_offset = (x + width) & 0x07;
i = (width + start_offset) / 8;
if (end_offset)
i++;
VGLPlane[0] = VGLBuf;
VGLPlane[1] = VGLPlane[0] + i;
VGLPlane[2] = VGLPlane[1] + i;
VGLPlane[3] = VGLPlane[2] + i;
pos = 0;
planepos = 0;
last = 8 - start_offset;
while (pos < width) {
word = 0;
while (pos < last && pos < width)
word = (word<<1) | color2bit[line[pos++]&0x0f];
VGLPlane[0][planepos] = word;
VGLPlane[1][planepos] = word>>8;
VGLPlane[2][planepos] = word>>16;
VGLPlane[3][planepos] = word>>24;
planepos++;
last += 8;
}
planepos--;
if (end_offset) {
word <<= (8 - end_offset);
VGLPlane[0][planepos] = word;
VGLPlane[1][planepos] = word>>8;
VGLPlane[2][planepos] = word>>16;
VGLPlane[3][planepos] = word>>24;
}
if (start_offset || end_offset)
width+=8;
width /= 8;
outb(0x3ce, 0x01); outb(0x3cf, 0x00); /* set/reset enable */
outb(0x3ce, 0x08); outb(0x3cf, 0xff); /* bit mask */
for (i=0; i<4; i++) {
outb(0x3c4, 0x02);
outb(0x3c5, 0x01<<i);
outb(0x3ce, 0x04);
outb(0x3cf, i);
pos = VGLAdpInfo.va_line_width*y + x/8;
if (dst->Type == VIDBUF4) {
if (end_offset)
VGLPlane[i][planepos] |= dst->Bitmap[pos+planepos] & mask[end_offset];
if (start_offset)
VGLPlane[i][0] |= dst->Bitmap[pos] & ~mask[start_offset];
bcopy(&VGLPlane[i][0], dst->Bitmap + pos, width);
} else { /* VIDBUF4S */
if (end_offset) {
offset = VGLSetSegment(pos + planepos);
VGLPlane[i][planepos] |= dst->Bitmap[offset] & mask[end_offset];
}
offset = VGLSetSegment(pos);
if (start_offset)
VGLPlane[i][0] |= dst->Bitmap[offset] & ~mask[start_offset];
for (last = width; ; ) {
len = min(VGLAdpInfo.va_window_size - offset, last);
bcopy(&VGLPlane[i][width - last], dst->Bitmap + offset, len);
pos += len;
last -= len;
if (last <= 0)
break;
offset = VGLSetSegment(pos);
}
}
}
break;
case VIDBUF8X:
address = dst->Bitmap + VGLAdpInfo.va_line_width * y + x/4;
for (i=0; i<4; i++) {
outb(0x3c4, 0x02);
outb(0x3c5, 0x01 << ((x + i)%4));
for (planepos=0, pos=i; pos<width; planepos++, pos+=4)
address[planepos] = line[pos];
if ((x + i)%4 == 3)
++address;
}
break;
case VIDBUF8S:
case VIDBUF16S:
case VIDBUF24S:
case VIDBUF32S:
width = width * dst->PixelBytes;
pos = (dst->VXsize * y + x) * dst->PixelBytes;
while (width > 0) {
offset = VGLSetSegment(pos);
i = min(VGLAdpInfo.va_window_size - offset, width);
bcopy(line, dst->Bitmap + offset, i);
line += i;
pos += i;
width -= i;
}
break;
case MEMBUF:
case VIDBUF8:
case VIDBUF16:
case VIDBUF24:
case VIDBUF32:
address = dst->Bitmap + (dst->VXsize * y + x) * dst->PixelBytes;
bcopy(line, address, width * dst->PixelBytes);
break;
default:
;
}
}
int
__VGLBitmapCopy(VGLBitmap *src, int srcx, int srcy,
VGLBitmap *dst, int dstx, int dsty, int width, int hight)
{
int srcline, dstline, yend, yextra, ystep;
if (srcx>src->VXsize || srcy>src->VYsize
|| dstx>dst->VXsize || dsty>dst->VYsize)
return -1;
if (srcx < 0) {
width=width+srcx; dstx-=srcx; srcx=0;
}
if (srcy < 0) {
hight=hight+srcy; dsty-=srcy; srcy=0;
}
if (dstx < 0) {
width=width+dstx; srcx-=dstx; dstx=0;
}
if (dsty < 0) {
hight=hight+dsty; srcy-=dsty; dsty=0;
}
if (srcx+width > src->VXsize)
width=src->VXsize-srcx;
if (srcy+hight > src->VYsize)
hight=src->VYsize-srcy;
if (dstx+width > dst->VXsize)
width=dst->VXsize-dstx;
if (dsty+hight > dst->VYsize)
hight=dst->VYsize-dsty;
if (width < 0 || hight < 0)
return -1;
yend = srcy + hight;
yextra = 0;
ystep = 1;
if (src->Bitmap == dst->Bitmap && srcy < dsty) {
yend = srcy;
yextra = hight - 1;
ystep = -1;
}
for (srcline = srcy + yextra, dstline = dsty + yextra; srcline != yend;
srcline += ystep, dstline += ystep) {
WriteVerticalLine(dst, dstx, dstline, width,
src->Bitmap+(srcline*src->VXsize+srcx)*dst->PixelBytes);
}
return 0;
}
int
VGLBitmapCopy(VGLBitmap *src, int srcx, int srcy,
VGLBitmap *dst, int dstx, int dsty, int width, int hight)
{
int error;
if (src == VGLDisplay)
src = &VGLVDisplay;
if (src->Type != MEMBUF)
return -1; /* invalid */
if (dst == VGLDisplay) {
VGLMouseFreeze(dstx, dsty, width, hight, 0);
__VGLBitmapCopy(src, srcx, srcy, &VGLVDisplay, dstx, dsty, width, hight);
src = &VGLVDisplay;
srcx = dstx;
srcy = dsty;
} else if (dst->Type != MEMBUF)
return -1; /* invalid */
error = __VGLBitmapCopy(src, srcx, srcy, dst, dstx, dsty, width, hight);
if (dst == VGLDisplay)
VGLMouseUnFreeze();
return error;
}
VGLBitmap
*VGLBitmapCreate(int type, int xsize, int ysize, byte *bits)
{
VGLBitmap *object;
if (type != MEMBUF)
return NULL;
if (xsize < 0 || ysize < 0)
return NULL;
object = (VGLBitmap *)malloc(sizeof(*object));
if (object == NULL)
return NULL;
object->Type = type;
object->Xsize = xsize;
object->Ysize = ysize;
object->VXsize = xsize;
object->VYsize = ysize;
object->Xorigin = 0;
object->Yorigin = 0;
object->Bitmap = bits;
object->PixelBytes = VGLDisplay->PixelBytes;
return object;
}
void
VGLBitmapDestroy(VGLBitmap *object)
{
if (object->Bitmap)
free(object->Bitmap);
free(object);
}
int
VGLBitmapAllocateBits(VGLBitmap *object)
{
object->Bitmap = malloc(object->VXsize*object->VYsize*object->PixelBytes);
if (object->Bitmap == NULL)
return -1;
return 0;
}