freebsd-dev/lib/libvgl/simple.c
Bruce Evans 014ddcbce4 Fix accessing pixels under the mouse cursor:
Reading of single pixels didn't look under the cursor.

Copying of 1x1 bitmaps didn't look under the cursor for either reading
or writing.

Copying of larger bitmaps looked under the cursor for at most the
destination.

Copying of larger bitmaps looked under a garbage cursor (for the Display
bitmap) when the destination is a MEMBUF.  The results are not used, so
this only wasted time and flickered the cursor.

Writing of single pixels looked under a garbage cursor for MEMBUF
destinations, as above except this clobbered the current cursor and
didn't update the MEMBUF.  Writing of single pixels is not implemented
yet in depths > 8.  Otherwise, writing of single pixels worked.  It was
the only working case for accessing pixels under the cursor.

Clearing of MEMBUFs wasted time freezing the cursor in the Display bitmap.

The fixes abuse the top bits in the color arg to the cursor freezing
function to control the function.  Also clear the top 8 bits so that
applications can't clobber the control bits or create 256 aliases for
every 24-bit pixel value in depth 32.

Races fixed:

Showing and hiding the cursor only tried to avoid races with the mouse
event signal handler for internal operations.  There are still many
shorter races from not using volatile or sig_atomic_t for the variable
to control this.  This variable also controls freezes, and has more
complicated states than before.

The internal operation of unfreezing the cursor opened a race window
by unsetting the signal/freeze variable before showing the cursor.
2019-03-27 18:03:34 +00:00

693 lines
18 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 <signal.h>
#include <sys/fbio.h>
#include "vgl.h"
static byte VGLSavePaletteRed[256];
static byte VGLSavePaletteGreen[256];
static byte VGLSavePaletteBlue[256];
#define ABS(a) (((a)<0) ? -(a) : (a))
#define SGN(a) (((a)<0) ? -1 : 1)
#define min(x, y) (((x) < (y)) ? (x) : (y))
#define max(x, y) (((x) > (y)) ? (x) : (y))
static void
color2mem(u_long color, byte *b, int len)
{
switch (len) {
case 4:
b[3] = (color >> 24) & 0xff;
/* fallthrough */
case 3:
b[2] = (color >> 16) & 0xff;
/* fallthrough */
case 2:
b[1] = (color >> 8) & 0xff;
/* fallthrough */
case 1:
default:
b[0] = color & 0xff;
break;
}
return;
}
static u_long
mem2color(byte *b, int len)
{
u_long color = 0;
switch (len) {
case 4:
color |= (b[3] & 0xff) << 24;
/* fallthrough */
case 3:
color |= (b[2] & 0xff) << 16;
/* fallthrough */
case 2:
color |= (b[1] & 0xff) << 8;
/* fallthrough */
case 1:
default:
color |= (b[0] & 0xff);
break;
}
return color;
}
void
VGLSetXY(VGLBitmap *object, int x, int y, u_long color)
{
int offset;
byte b[4];
VGLCheckSwitch();
if (x>=0 && x<object->VXsize && y>=0 && y<object->VYsize) {
if (object->Type == MEMBUF ||
!VGLMouseFreeze(x, y, 1, 1, 0x80000000 | color)) {
switch (object->Type) {
case MEMBUF:
case VIDBUF8:
object->Bitmap[y*object->VXsize+x]=((byte)color);
break;
case VIDBUF8S:
object->Bitmap[VGLSetSegment(y*object->VXsize+x)]=((byte)color);
break;
case VIDBUF16:
case VIDBUF24:
case VIDBUF32:
color2mem(color, b, object->PixelBytes);
bcopy(b, &object->Bitmap[(y*object->VXsize+x) * object->PixelBytes],
object->PixelBytes);
break;
case VIDBUF16S:
case VIDBUF24S:
case VIDBUF32S:
color2mem(color, b, object->PixelBytes);
offset = VGLSetSegment((y*object->VXsize+x) * object->PixelBytes);
bcopy(b, &object->Bitmap[offset], object->PixelBytes);
break;
case VIDBUF8X:
outb(0x3c4, 0x02);
outb(0x3c5, 0x01 << (x&0x3));
object->Bitmap[(unsigned)(VGLAdpInfo.va_line_width*y)+(x/4)] = ((byte)color);
break;
case VIDBUF4S:
offset = VGLSetSegment(y*VGLAdpInfo.va_line_width + x/8);
goto set_planar;
case VIDBUF4:
offset = y*VGLAdpInfo.va_line_width + x/8;
set_planar:
outb(0x3c4, 0x02); outb(0x3c5, 0x0f);
outb(0x3ce, 0x00); outb(0x3cf, (byte)color & 0x0f); /* set/reset */
outb(0x3ce, 0x01); outb(0x3cf, 0x0f); /* set/reset enable */
outb(0x3ce, 0x08); outb(0x3cf, 0x80 >> (x%8)); /* bit mask */
object->Bitmap[offset] |= (byte)color;
}
}
if (object->Type != MEMBUF)
VGLMouseUnFreeze();
}
}
static u_long
__VGLGetXY(VGLBitmap *object, int x, int y)
{
int offset;
byte b[4];
int i;
u_long color;
byte mask;
switch (object->Type) {
case MEMBUF:
case VIDBUF8:
return object->Bitmap[((y*object->VXsize)+x)];
case VIDBUF8S:
return object->Bitmap[VGLSetSegment(y*object->VXsize+x)];
case VIDBUF16:
case VIDBUF24:
case VIDBUF32:
bcopy(&object->Bitmap[(y*object->VXsize+x) * object->PixelBytes],
b, object->PixelBytes);
return (mem2color(b, object->PixelBytes));
case VIDBUF16S:
case VIDBUF24S:
case VIDBUF32S:
offset = VGLSetSegment((y*object->VXsize+x) * object->PixelBytes);
bcopy(&object->Bitmap[offset], b, object->PixelBytes);
return (mem2color(b, object->PixelBytes));
case VIDBUF8X:
outb(0x3ce, 0x04); outb(0x3cf, x & 0x3);
return object->Bitmap[(unsigned)(VGLAdpInfo.va_line_width*y)+(x/4)];
case VIDBUF4S:
offset = VGLSetSegment(y*VGLAdpInfo.va_line_width + x/8);
goto get_planar;
case VIDBUF4:
offset = y*VGLAdpInfo.va_line_width + x/8;
get_planar:
color = 0;
mask = 0x80 >> (x%8);
for (i = 0; i < VGLModeInfo.vi_planes; i++) {
outb(0x3ce, 0x04); outb(0x3cf, i);
color |= (((volatile VGLBitmap *)object)->Bitmap[offset] & mask) ?
(1 << i) : 0;
}
return color;
}
return 0; /* XXX black? */
}
u_long
VGLGetXY(VGLBitmap *object, int x, int y)
{
u_long color;
VGLCheckSwitch();
if (x<0 || x>=object->VXsize || y<0 || y>=object->VYsize)
return 0;
if (object->Type != MEMBUF) {
color = VGLMouseFreeze(x, y, 1, 1, 0x40000000);
if (color & 0x40000000) {
VGLMouseUnFreeze();
return color & 0xffffff;
}
}
color = __VGLGetXY(object, x, y);
if (object->Type != MEMBUF)
VGLMouseUnFreeze();
return color;
}
/*
* Symmetric Double Step Line Algorithm by Brian Wyvill from
* "Graphics Gems", Academic Press, 1990.
*/
#define SL_SWAP(a,b) {a^=b; b^=a; a^=b;}
#define SL_ABSOLUTE(i,j,k) ( (i-j)*(k = ( (i-j)<0 ? -1 : 1)))
void
plot(VGLBitmap * object, int x, int y, int flag, byte color)
{
/* non-zero flag indicates the pixels need swapping back. */
if (flag)
VGLSetXY(object, y, x, color);
else
VGLSetXY(object, x, y, color);
}
void
VGLLine(VGLBitmap *object, int x1, int y1, int x2, int y2, u_long color)
{
int dx, dy, incr1, incr2, D, x, y, xend, c, pixels_left;
int sign_x, sign_y, step, reverse, i;
dx = SL_ABSOLUTE(x2, x1, sign_x);
dy = SL_ABSOLUTE(y2, y1, sign_y);
/* decide increment sign by the slope sign */
if (sign_x == sign_y)
step = 1;
else
step = -1;
if (dy > dx) { /* chooses axis of greatest movement (make dx) */
SL_SWAP(x1, y1);
SL_SWAP(x2, y2);
SL_SWAP(dx, dy);
reverse = 1;
} else
reverse = 0;
/* note error check for dx==0 should be included here */
if (x1 > x2) { /* start from the smaller coordinate */
x = x2;
y = y2;
/* x1 = x1;
y1 = y1; */
} else {
x = x1;
y = y1;
x1 = x2;
y1 = y2;
}
/* Note dx=n implies 0 - n or (dx+1) pixels to be set */
/* Go round loop dx/4 times then plot last 0,1,2 or 3 pixels */
/* In fact (dx-1)/4 as 2 pixels are already plotted */
xend = (dx - 1) / 4;
pixels_left = (dx - 1) % 4; /* number of pixels left over at the
* end */
plot(object, x, y, reverse, color);
if (pixels_left < 0)
return; /* plot only one pixel for zero length
* vectors */
plot(object, x1, y1, reverse, color); /* plot first two points */
incr2 = 4 * dy - 2 * dx;
if (incr2 < 0) { /* slope less than 1/2 */
c = 2 * dy;
incr1 = 2 * c;
D = incr1 - dx;
for (i = 0; i < xend; i++) { /* plotting loop */
++x;
--x1;
if (D < 0) {
/* pattern 1 forwards */
plot(object, x, y, reverse, color);
plot(object, ++x, y, reverse, color);
/* pattern 1 backwards */
plot(object, x1, y1, reverse, color);
plot(object, --x1, y1, reverse, color);
D += incr1;
} else {
if (D < c) {
/* pattern 2 forwards */
plot(object, x, y, reverse, color);
plot(object, ++x, y += step, reverse,
color);
/* pattern 2 backwards */
plot(object, x1, y1, reverse, color);
plot(object, --x1, y1 -= step, reverse,
color);
} else {
/* pattern 3 forwards */
plot(object, x, y += step, reverse, color);
plot(object, ++x, y, reverse, color);
/* pattern 3 backwards */
plot(object, x1, y1 -= step, reverse,
color);
plot(object, --x1, y1, reverse, color);
}
D += incr2;
}
} /* end for */
/* plot last pattern */
if (pixels_left) {
if (D < 0) {
plot(object, ++x, y, reverse, color); /* pattern 1 */
if (pixels_left > 1)
plot(object, ++x, y, reverse, color);
if (pixels_left > 2)
plot(object, --x1, y1, reverse, color);
} else {
if (D < c) {
plot(object, ++x, y, reverse, color); /* pattern 2 */
if (pixels_left > 1)
plot(object, ++x, y += step, reverse, color);
if (pixels_left > 2)
plot(object, --x1, y1, reverse, color);
} else {
/* pattern 3 */
plot(object, ++x, y += step, reverse, color);
if (pixels_left > 1)
plot(object, ++x, y, reverse, color);
if (pixels_left > 2)
plot(object, --x1, y1 -= step, reverse, color);
}
}
} /* end if pixels_left */
}
/* end slope < 1/2 */
else { /* slope greater than 1/2 */
c = 2 * (dy - dx);
incr1 = 2 * c;
D = incr1 + dx;
for (i = 0; i < xend; i++) {
++x;
--x1;
if (D > 0) {
/* pattern 4 forwards */
plot(object, x, y += step, reverse, color);
plot(object, ++x, y += step, reverse, color);
/* pattern 4 backwards */
plot(object, x1, y1 -= step, reverse, color);
plot(object, --x1, y1 -= step, reverse, color);
D += incr1;
} else {
if (D < c) {
/* pattern 2 forwards */
plot(object, x, y, reverse, color);
plot(object, ++x, y += step, reverse,
color);
/* pattern 2 backwards */
plot(object, x1, y1, reverse, color);
plot(object, --x1, y1 -= step, reverse,
color);
} else {
/* pattern 3 forwards */
plot(object, x, y += step, reverse, color);
plot(object, ++x, y, reverse, color);
/* pattern 3 backwards */
plot(object, x1, y1 -= step, reverse, color);
plot(object, --x1, y1, reverse, color);
}
D += incr2;
}
} /* end for */
/* plot last pattern */
if (pixels_left) {
if (D > 0) {
plot(object, ++x, y += step, reverse, color); /* pattern 4 */
if (pixels_left > 1)
plot(object, ++x, y += step, reverse,
color);
if (pixels_left > 2)
plot(object, --x1, y1 -= step, reverse,
color);
} else {
if (D < c) {
plot(object, ++x, y, reverse, color); /* pattern 2 */
if (pixels_left > 1)
plot(object, ++x, y += step, reverse, color);
if (pixels_left > 2)
plot(object, --x1, y1, reverse, color);
} else {
/* pattern 3 */
plot(object, ++x, y += step, reverse, color);
if (pixels_left > 1)
plot(object, ++x, y, reverse, color);
if (pixels_left > 2) {
if (D > c) /* step 3 */
plot(object, --x1, y1 -= step, reverse, color);
else /* step 2 */
plot(object, --x1, y1, reverse, color);
}
}
}
}
}
}
void
VGLBox(VGLBitmap *object, int x1, int y1, int x2, int y2, u_long color)
{
VGLLine(object, x1, y1, x2, y1, color);
VGLLine(object, x2, y1, x2, y2, color);
VGLLine(object, x2, y2, x1, y2, color);
VGLLine(object, x1, y2, x1, y1, color);
}
void
VGLFilledBox(VGLBitmap *object, int x1, int y1, int x2, int y2, u_long color)
{
int y;
for (y=y1; y<=y2; y++) VGLLine(object, x1, y, x2, y, color);
}
static inline void
set4pixels(VGLBitmap *object, int x, int y, int xc, int yc, u_long color)
{
if (x!=0) {
VGLSetXY(object, xc+x, yc+y, color);
VGLSetXY(object, xc-x, yc+y, color);
if (y!=0) {
VGLSetXY(object, xc+x, yc-y, color);
VGLSetXY(object, xc-x, yc-y, color);
}
}
else {
VGLSetXY(object, xc, yc+y, color);
if (y!=0)
VGLSetXY(object, xc, yc-y, color);
}
}
void
VGLEllipse(VGLBitmap *object, int xc, int yc, int a, int b, u_long color)
{
int x = 0, y = b, asq = a*a, asq2 = a*a*2, bsq = b*b;
int bsq2 = b*b*2, d = bsq-asq*b+asq/4, dx = 0, dy = asq2*b;
while (dx<dy) {
set4pixels(object, x, y, xc, yc, color);
if (d>0) {
y--; dy-=asq2; d-=dy;
}
x++; dx+=bsq2; d+=bsq+dx;
}
d+=(3*(asq-bsq)/2-(dx+dy))/2;
while (y>=0) {
set4pixels(object, x, y, xc, yc, color);
if (d<0) {
x++; dx+=bsq2; d+=dx;
}
y--; dy-=asq2; d+=asq-dy;
}
}
static inline void
set2lines(VGLBitmap *object, int x, int y, int xc, int yc, u_long color)
{
if (x!=0) {
VGLLine(object, xc+x, yc+y, xc-x, yc+y, color);
if (y!=0)
VGLLine(object, xc+x, yc-y, xc-x, yc-y, color);
}
else {
VGLLine(object, xc, yc+y, xc, yc-y, color);
}
}
void
VGLFilledEllipse(VGLBitmap *object, int xc, int yc, int a, int b, u_long color)
{
int x = 0, y = b, asq = a*a, asq2 = a*a*2, bsq = b*b;
int bsq2 = b*b*2, d = bsq-asq*b+asq/4, dx = 0, dy = asq2*b;
while (dx<dy) {
set2lines(object, x, y, xc, yc, color);
if (d>0) {
y--; dy-=asq2; d-=dy;
}
x++; dx+=bsq2; d+=bsq+dx;
}
d+=(3*(asq-bsq)/2-(dx+dy))/2;
while (y>=0) {
set2lines(object, x, y, xc, yc, color);
if (d<0) {
x++; dx+=bsq2; d+=dx;
}
y--; dy-=asq2; d+=asq-dy;
}
}
void
VGLClear(VGLBitmap *object, u_long color)
{
int offset;
int len;
int i, total = 0;
byte b[4];
VGLCheckSwitch();
if (object->Type != MEMBUF)
VGLMouseFreeze(0, 0, object->Xsize, object->Ysize, color);
switch (object->Type) {
case MEMBUF:
case VIDBUF8:
memset(object->Bitmap, (byte)color, object->VXsize*object->VYsize);
break;
case VIDBUF8S:
for (offset = 0; offset < object->VXsize*object->VYsize; ) {
VGLSetSegment(offset);
len = min(object->VXsize*object->VYsize - offset,
VGLAdpInfo.va_window_size);
memset(object->Bitmap, (byte)color, len);
offset += len;
}
break;
case VIDBUF16:
case VIDBUF24:
case VIDBUF32:
color2mem(color, b, object->PixelBytes);
total = object->VXsize*object->VYsize*object->PixelBytes;
for (i = 0; i < total; i += object->PixelBytes)
bcopy(b, object->Bitmap + i, object->PixelBytes);
break;
case VIDBUF16S:
case VIDBUF24S:
case VIDBUF32S:
color2mem(color, b, object->PixelBytes);
total = object->VXsize*object->VYsize*object->PixelBytes;
for (offset = 0; offset < total; ) {
VGLSetSegment(offset);
len = min(total - offset, VGLAdpInfo.va_window_size);
for (i = 0; i < len; i += object->PixelBytes)
bcopy(object->Bitmap + (offset + i) % VGLAdpInfo.va_window_size, b,
object->PixelBytes);
offset += len;
}
break;
case VIDBUF8X:
/* XXX works only for Xsize % 4 = 0 */
outb(0x3c6, 0xff);
outb(0x3c4, 0x02); outb(0x3c5, 0x0f);
memset(object->Bitmap, (byte)color, VGLAdpInfo.va_line_width*object->VYsize);
break;
case VIDBUF4:
case VIDBUF4S:
/* XXX works only for Xsize % 8 = 0 */
outb(0x3c4, 0x02); outb(0x3c5, 0x0f);
outb(0x3ce, 0x05); outb(0x3cf, 0x02); /* mode 2 */
outb(0x3ce, 0x01); outb(0x3cf, 0x00); /* set/reset enable */
outb(0x3ce, 0x08); outb(0x3cf, 0xff); /* bit mask */
for (offset = 0; offset < VGLAdpInfo.va_line_width*object->VYsize; ) {
VGLSetSegment(offset);
len = min(object->VXsize*object->VYsize - offset,
VGLAdpInfo.va_window_size);
memset(object->Bitmap, (byte)color, len);
offset += len;
}
outb(0x3ce, 0x05); outb(0x3cf, 0x00);
break;
}
if (object->Type != MEMBUF)
VGLMouseUnFreeze();
}
void
VGLRestorePalette()
{
int i;
outb(0x3C6, 0xFF);
inb(0x3DA);
outb(0x3C8, 0x00);
for (i=0; i<256; i++) {
outb(0x3C9, VGLSavePaletteRed[i]);
inb(0x84);
outb(0x3C9, VGLSavePaletteGreen[i]);
inb(0x84);
outb(0x3C9, VGLSavePaletteBlue[i]);
inb(0x84);
}
inb(0x3DA);
outb(0x3C0, 0x20);
}
void
VGLSavePalette()
{
int i;
outb(0x3C6, 0xFF);
inb(0x3DA);
outb(0x3C7, 0x00);
for (i=0; i<256; i++) {
VGLSavePaletteRed[i] = inb(0x3C9);
inb(0x84);
VGLSavePaletteGreen[i] = inb(0x3C9);
inb(0x84);
VGLSavePaletteBlue[i] = inb(0x3C9);
inb(0x84);
}
inb(0x3DA);
outb(0x3C0, 0x20);
}
void
VGLSetPalette(byte *red, byte *green, byte *blue)
{
int i;
for (i=0; i<256; i++) {
VGLSavePaletteRed[i] = red[i];
VGLSavePaletteGreen[i] = green[i];
VGLSavePaletteBlue[i] = blue[i];
}
VGLCheckSwitch();
outb(0x3C6, 0xFF);
inb(0x3DA);
outb(0x3C8, 0x00);
for (i=0; i<256; i++) {
outb(0x3C9, VGLSavePaletteRed[i]);
inb(0x84);
outb(0x3C9, VGLSavePaletteGreen[i]);
inb(0x84);
outb(0x3C9, VGLSavePaletteBlue[i]);
inb(0x84);
}
inb(0x3DA);
outb(0x3C0, 0x20);
}
void
VGLSetPaletteIndex(byte color, byte red, byte green, byte blue)
{
VGLSavePaletteRed[color] = red;
VGLSavePaletteGreen[color] = green;
VGLSavePaletteBlue[color] = blue;
VGLCheckSwitch();
outb(0x3C6, 0xFF);
inb(0x3DA);
outb(0x3C8, color);
outb(0x3C9, red); outb(0x3C9, green); outb(0x3C9, blue);
inb(0x3DA);
outb(0x3C0, 0x20);
}
void
VGLSetBorder(byte color)
{
VGLCheckSwitch();
inb(0x3DA);
outb(0x3C0,0x11); outb(0x3C0, color);
inb(0x3DA);
outb(0x3C0, 0x20);
}
void
VGLBlankDisplay(int blank)
{
byte val;
VGLCheckSwitch();
outb(0x3C4, 0x01); val = inb(0x3C5); outb(0x3C4, 0x01);
outb(0x3C5, ((blank) ? (val |= 0x20) : (val &= 0xDF)));
}