/***************************************************/
/* */
/* Demonstration program to transfrom images for */
/* 320 x 200 256 color mode, Borland C */
/* Christopher Dean 05/10/93 */
/* */
/***************************************************/
#include <stdio.h>
#include <stdlib.h>
#include <graphics.h>
#include <string.h>
#include <stdlib.h>
#include <dos.h>
#include <conio.h>
#include <alloc.h>
#include <process.h>
#include <bios.h>
#include <math.h>
/* key defines */
#define KEY_END 0x4f00
#define KEY_DOWN 0x5000
#define KEY_LEFT 0x4b00
#define KEY_RIGHT 0x4d00
#define KEY_UP 0x4800
/* direction defines */
#define SHEAR_VERT_RIGHT 0
#define SHEAR_VERT_LEFT 1
#define SHEAR_HORZ_RIGHT 1
#define SHEAR_HORZ_LEFT 0
/* function prototypes for transformation routines */
extern char *TransXY(char *buffer,int width,
int height,int newwidth,int newheight);
extern char *ShearVert(char *buffer,int width,
int height,int newwidth,int newheight);
extern char *ShearHorz(char *buffer,int width,
int height,int newwidth,int newheight);
/* detect the VGA256.BGI driver */
static int huge DetectVGA256(void)
{
int DetectedDriver;
int SuggestedMode;
detectgraph(&DetectedDriver,&SuggestedMode);
if ((DetectedDriver == VGA) ||
(DetectedDriver == MCGA))
return(0);
else
return (grError);
}
/* initialize the 320 x 200 256 color mode */
void InitGraphics (void)
{
int GraphMode;
int GraphDriver = DETECT;
detectgraph(&GraphDriver,&GraphMode);
if ((GraphDriver == MCGA) ||
(GraphDriver == VGA)) {
GraphDriver = MCGA;
GraphMode = MCGAC0;
installuserdriver("VGA256",DetectVGA256);
GraphDriver = DETECT;
initgraph(&GraphDriver,&GraphMode,"");
}
}
/* my own version of the Borland C putimage function. If
the color in the buffer is 255 then it does not
put anything, the background color remains. */
void xputimage(int left,int top,void far *bitmap)
{
int y,i;
int width,height; /* dimensions of image */
char *w; /* pointer to screen */
char *bitmap1;
unsigned char c;
/* get image dimensions from buffer and set bitmap1
to start of image */
width = *((int *)bitmap);
height = *((int *)bitmap+1);
bitmap1 = (char *) bitmap+4;
/* set screen pointer */
w = (char far *) 0xA0000000L + ((long)top * 320L) +
(long)left;
/* loop through rows of the image, placing them on
the screen */
for (y=top;y<top+height;y++) {
for (i = 0; i < width; ++i) {
c = *((char *) bitmap1);
++bitmap1;
if (c != 0xff) /* preserve the background? */
*(w+(long) i) = c;
/* just for the demo set the background to
black. Leave this out if you want to
preserve the background. */
else *(w+(long) i) = 0;
}
w += 320L; /* next row on screen */
}
}
main()
{
int i,j;
char *newpic,*newpic1,*newpic2=NULL;
int w,h,nw,nh,nw1,nh1; /* image dimensions */
char text[40];
int key,valid_key,option;
do {
printf("\n\nDemonstration functions:\n\n");
printf("%s\n%s\n%s\n%s\n%s\n%s\n%s\n\n",
" 1) Scaling",
" 2) Vertical Shearing Right",
" 3) Vertical Shearing Left",
" 4) Horizontal Shearing Right",
" 5) Horzontal Shearing Left",
" 6) Rotations",
" 7) Exit" );
key = getch();
valid_key = 1;
switch(key) {
case '1':
option = 0;
break;
case '2':
option = 1;
break;
case '3':
option = 2;
break;
case '4':
option = 3;
break;
case '5':
option = 4;
break;
case '6':
option = 5;
break;
case '7':
option = 6;
break;
default:
valid_key = 0;
}
}
while (!valid_key);
if (option == 6)
exit(0);
InitGraphics(); /* Initialize graphics */
/* draw the house */
setfillstyle(SOLID_FILL,0);
bar(0,0,319,199);
setcolor(15);
setlinestyle(SOLID_LINE,0,THICK_WIDTH);
rectangle(91,71,171,121);
line(1,21,91,71);
line(1,71,91,121);
line(1,21,1,71);
line(1,21,41,1);
line(41,1,131,51);
line(131,51,171,71);
line(91,71,131,51);
setcolor(2);
rectangle(121,96,141,121);
newpic = malloc(imagesize(0,0,182,134));
getimage(0,0,182,134,newpic);
/* initialize dimensions */
nw = nw1 = w = *((int *) newpic);
nh = nh1 = h = *((int *) newpic+1);
setcolor(15);
sprintf(text,"width: %d height: %d",nw,nh);
outtextxy(10,190,text);
while ((key= bioskey(0)) != KEY_END) {
switch(option) {
case 0:
/* scaling */
switch(key) {
case KEY_LEFT:
/* decrease width */
bar(nw,1,nw-5,1+nh);
nw -= 5;
if (nw < 1) /* keep within screen */
nw = 1;
break;
case KEY_RIGHT:
/* increase width */
nw = nw + 5;
if (nw > 318) /* keep within screen */
nw = 318;
break;
case KEY_UP:
/* decrease height */
bar(1,nh,1+nw,nh-5);
nh -= 5;
if (nh < 1)
nh = 1;
break;
case KEY_DOWN:
/* increase height */
nh = nh + 5;
if (nh > 189)
nh = 189;
break;
}
/* change size */
newpic1 = TransXY(newpic,w,h,nw,nh);
break;
case 1:
case 2:
/* vertical shearing */
switch(key) {
case KEY_DOWN:
/* increase height of shear */
nh += 5;
if (nh > 189)
nh = 189;
break;
case KEY_UP:
/* decrease height of shear */
bar(1,1+nh,1+w,nh-4);
nh -= 5;
if (nh < h)
nh = h;
break;
}
if (option == 1)
newpic1 = ShearVert(newpic,w,h,nh,SHEAR_VERT_RIGHT);
else
newpic1 = ShearVert(newpic,w,h,nh,SHEAR_VERT_LEFT);
break;
case 3:
case 4:
/* horizontal shearing */
switch(key) {
case KEY_RIGHT:
/* increase width of shear */
nw += 5;
if (nw > 318)
nw = 318;
break;
case KEY_LEFT:
/* decrease width of shear */
bar(1+nw,1,nw-4,1+h);
nw -= 5;
if (nw < w)
nw = w;
break;
}
if (option == 4)
newpic1 = ShearHorz(newpic,w,h,nw,SHEAR_HORZ_LEFT);
else
newpic1 = ShearHorz(newpic,w,h,nw,SHEAR_HORZ_RIGHT);
break;
case 5:
/* rotations */
switch(key) {
/* rotate clockwise */
case KEY_RIGHT:
if (nw <= 273)
nw += 5;
else nh -= 5;
if (nw < w) {
/* handle case when we have previously
been rotating counter-clockwise */
/* make sure we always shear >
width of image */
nw1 = w + w - nw;
newpic2 = ShearHorz(newpic,w,h,nw1,
SHEAR_HORZ_RIGHT);
nh += 5;
/* make sure we always shear >
height of image */
nh1 = h + h - nh;
newpic1 = ShearVert(newpic2,nw1,h,
nh1,SHEAR_VERT_LEFT);
}
else {
newpic2 = ShearHorz(newpic,w,h,nw,
SHEAR_HORZ_LEFT);
nh += 5;
newpic1 = ShearVert(newpic2,nw,h,
nh,SHEAR_VERT_RIGHT);
}
break;
case KEY_LEFT:
/* rotate counter-clockwise */
if (nw1 <= 273)
nw -= 5;
else nh += 5;
if (nw < w) {
nw1 = w + w - nw;
newpic2 = ShearHorz(newpic,w,h,nw1,SHEAR_HORZ_RIGHT);
nh -= 5;
nh1 = h + h - nh;
newpic1 = ShearVert(newpic2,nw1,hnh1,SHEAR_VERT_LEFT);
}
else {
/* handle case when we have
previously been rotating
clockwise */
newpic2 = ShearHorz(newpic,w,h,nw,SHEAR_HORZ_LEFT);
nh -= 5;
newpic1 = ShearVert(newpic2,nw,h,nh,SHEAR_VERT_RIGHT);
}
break;
}
}
xputimage(0,0,newpic1);
setcolor(15);
if ((option == 5) && (nw < w))
/* use different dimensions for rotation */
sprintf(text,"width: %d height: %d",nw1,nh1);
else
sprintf(text,"width: %d height: %d",nw,nh);
bar(10,190,300,199);
outtextxy(10,190,text);
free(newpic1);
if (newpic2 != NULL) {
free(newpic2);
newpic2 = NULL;
}
}
closegraph(); /* shut down graphics */
textmode(LASTMODE); /* restore old textmode */
free(newpic);
}
/* End of File */