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test.cpp
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/* sdlbgidemo.c -*- C -*-
*
* To compile:
* gcc -o sdlbgidemo sdlbgidemo.c -lSDL_bgi -lSDL2 -lm
*
* By Guido Gonzato, June 2018.
*
* 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., 675 Mass Ave, Cambridge, MA 02139, USA.
*
*/
#include <graphics.h>
#define PI_CONV (3.1415926 / 180.0)
int
maxx, maxy,
width, height;
int gd, gm;
struct viewporttype viewport;
void wait (int);
void get_click (void);
void ket_key (void);
void pause (void);
void init_sdlbgi (void);
void message (char *str);
void mainwindow (void);
// -----
void wait (int msec)
{
int stop = 0;
Uint32
ticks,
now = SDL_GetTicks ();
while (! stop) {
if (kbhit ())
stop = 1;
ticks = SDL_GetTicks ();
if (ticks - now > msec)
stop = 1;
}
} // wait ()
// -----
void get_click (void)
{
// wait for a mouse click
while (! ismouseclick (WM_LBUTTONDOWN))
;
while (ismouseclick (WM_LBUTTONDOWN))
;
} // get_click ()
// -----
void pause (void)
{
// pause and exit if right click
int
stop = 0;
while (! stop) {
if (ismouseclick (WM_LBUTTONDOWN))
stop = 1;
if (ismouseclick (WM_RBUTTONDOWN)) {
closegraph ();
exit (1);
}
}
while (ismouseclick (WM_LBUTTONDOWN))
;
} // pause ()
// -----
void init_sdlbgi (void)
{
// initialise SDL_bgi system
setwinoptions ("",
SDL_WINDOWPOS_UNDEFINED,
SDL_WINDOWPOS_UNDEFINED,
SDL_WINDOW_FULLSCREEN);
detectgraph (&gd, &gm);
initgraph (&gd, &gm, "");
sdlbgifast ();
maxx = getmaxx ();
maxy = getmaxy ();
} // initgraph ()
// -----
void message (char *str)
{
// output a message at the screen bottom
setviewport (0, 0, maxx, maxy, 0);
setbkcolor (COLOR (40, 0, 0));
cleardevice ();
setcolor (YELLOW);
settextstyle (DEFAULT_FONT, HORIZ_DIR, 1);
settextjustify (CENTER_TEXT, CENTER_TEXT);
outtextxy (maxx / 2, 10, str);
setcolor (WHITE);
outtextxy (maxx / 2, maxy - 10,
"=== Left click to continue, right click to exit ===");
refresh ();
} // message ()
// -----
void mainwindow (void)
{
// set up main window
setcolor (WHITE);
setviewport (0, 0, maxx, maxy, 1);
rectangle (39, 19, maxx - 39, maxy - 19);
setviewport (40, 20, maxx - 40, maxy - 20, 1);
getviewsettings (&viewport);
setbkcolor (COLOR (0, 0, 20));
clearviewport ();
refresh ();
width = viewport.right - viewport.left + 1;
height = viewport.bottom - viewport.top + 1;
}
// -----
Uint32 speedtest (void)
{
Uint32
start, pixels = 0;
start = SDL_GetTicks ();
do {
putpixel (random (maxx), random (maxy), random (MAXCOLORS));
pixels++;
} while (SDL_GetTicks () < start + 1000);
clearviewport ();
return (pixels);
}
// -----
void load_logo ()
{
setwinoptions ("",
SDL_WINDOWPOS_CENTERED,
SDL_WINDOWPOS_CENTERED,
SDL_WINDOW_BORDERLESS);
initwindow (440, 150);
readimagefile ("logo.bmp", 0, 0, 440, 150);
wait (2000);
closewindow (0);
}
// -----
void sdlbgi_info (void)
{
// display information on SDL_bgi settings
char
str[1024];
struct linesettingstype
lineinfo;
struct fillsettingstype
fillinfo;
struct textsettingstype
textinfo;
struct palettetype
palette;
Uint32
pixels_per_second;
char *driver, *mode;
int x, y, dy;
message ("Please wait one second...");
pixels_per_second = speedtest ();
message ("Information on SDL_bgi Graphics");
mainwindow ();
setcolor (RED);
settextstyle (DEFAULT_FONT, HORIZ_DIR, 2);
settextjustify (RIGHT_TEXT, TOP_TEXT);
getviewsettings (&viewport); // get viewport info
getlinesettings (&lineinfo); // line style info
getfillsettings (&fillinfo); // fill style info
gettextsettings (&textinfo); // text style info
getpalette (&palette );
driver = getdrivername ();
mode = getmodename (gm);
x = width / 2; // screen centre
y = 40;
dy = textheight ("X") * 3;
outtextxy (x, y += dy, "Graphics device: ");
outtextxy (x, y += dy, "Graphics mode: ");
outtextxy (x, y += dy, "Screen resolution: ");
outtextxy (x, y += dy, "Current viewport: ");
outtextxy (x, y += dy, "Viewport clipping: ");
outtextxy (x, y += dy, "Current background colour: ");
outtextxy (x, y += dy, "Current foreground colour: ");
outtextxy (x, y += dy, "Current fill colour: ");
outtextxy (x, y += dy, "Character size: ");
outtextxy (x, y += dy, "Available pages: ");
outtextxy (x, y += dy, "Pixels per second: ");
settextjustify (LEFT_TEXT, TOP_TEXT);
y = 40;
setcolor (COLOR (240, 240, 0));
sprintf (str, "%s", driver);
outtextxy (x, y += dy, str);
sprintf (str, "%s", mode);
outtextxy (x, y += dy, str);
sprintf (str, "%d x %d", maxx + 1, maxy + 1);
outtextxy (x, y += dy, str);
sprintf (str, "(%d, %d) - (%d, %d)",
viewport.left, viewport.top,
viewport.right, viewport.bottom);
outtextxy (x, y += dy, str);
sprintf (str, "%s", viewport.clip ? "ON" : "OFF");
outtextxy (x, y += dy, str);
sprintf (str, "0x%02X%02X%02X",
RED_VALUE (getbkcolor ()),
GREEN_VALUE (getbkcolor ()),
BLUE_VALUE (getbkcolor ()));
outtextxy (x, y += dy, str);
sprintf (str, "0x%02X%02X%02X",
RED_VALUE (getcolor ()),
GREEN_VALUE (getcolor ()),
BLUE_VALUE (getcolor ()));
outtextxy (x, y += dy, str);
sprintf (str, "0x%02X%02X%02X",
RED_VALUE (fillinfo.color),
GREEN_VALUE (fillinfo.color),
BLUE_VALUE (fillinfo.color));
outtextxy (x, y += dy, str);
sprintf (str, "%d", textinfo.charsize);
outtextxy (x, y += dy, str);
sprintf (str, "%d", VPAGES);
outtextxy (x, y += dy, str);
sprintf (str, "%d", pixels_per_second);
outtextxy (x, y += dy, str);
refresh ();
pause ();
} // sdlbgi_info ()
// -----
void modedemo ()
{
int
dx, y, size;
void
*m;
message ("Plotting Bitwise Operators Demonstration");
mainwindow ();
getviewsettings (&viewport);
dx = (viewport.right - viewport.left - 100) / 5;
y = (viewport.bottom - viewport.top) / 3;
/* draw a red rectangle and store it */
settextjustify (LEFT_TEXT, TOP_TEXT);
setfillstyle (SOLID_FILL, RED);
bar (50, y, 50 + dx - 10, y + dx - 10);
size = imagesize (50, y, 50 + dx - 10, y + dx - 10);
m = malloc (size);
getimage (50, y, 50 + dx - 10, y + dx - 10, m);
/* draw five yellow rectangles */
setcolor (WHITE);
setfillstyle (SOLID_FILL, YELLOW);
for (int i = 0 ; i < 5; i++)
bar (50 + i*dx, y, 50 + i*dx + dx - 10, y + dx - 10);
outtextxy (50 + 0*dx, y - 20, "COPY_PUT");
outtextxy (50 + 1*dx, y - 20, "XOR_PUT");
outtextxy (50 + 2*dx, y - 20, "OR_PUT");
outtextxy (50 + 3*dx, y - 20, "AND_PUT");
outtextxy (50 + 4*dx, y - 20, "NOT_PUT");
setcolor (BLACK);
outtextxy (60, y + 10, "ffff00 (yellow)");
// COPY_PUT: red: ff0000
putimage (50 + 0*dx, y + dx/2, m, COPY_PUT);
outtextxy (60 + 0*dx, y + dx/2 + 20, "ff0000");
outtextxy (60 + 0*dx, y + dx/2 + 30, "(red)");
// XOR_PUT: red xor yellow: ff0000 ^ ffff00 = 00ff00 (green)
putimage (50 + 1*dx, y + dx/2, m, XOR_PUT);
outtextxy (60 + 1*dx, y + dx/2 + 20, "ff0000 ^ ffff00 = 00ff00");
outtextxy (60 + 1*dx, y + dx/2 + 30, "(green)");
// OR_PUT: red or yellow: ff0000 | ffff00 = ffff00 (yellow)
putimage (50 + 2*dx, y + dx/2, m, OR_PUT);
outtextxy (60 + 2*dx, y + dx/2 + 20, "ff0000 | ffff00 = ffff00");
outtextxy (60 + 2*dx, y + dx/2 + 30, "(yellow)");
// AND_PUT: red and yellow: ff0000 & ffff00 = ff0000 (red)
putimage (50 + 3*dx, y + dx/2, m, AND_PUT);
outtextxy (60 + 3*dx, y + dx/2 + 20, "ff0000 & ffff00 = 00ff00");
outtextxy (60 + 3*dx, y + dx/2 + 30, "(red)");
// NOT_PUT: ~ red: 00ffff (cyan)
putimage (50 + 4*dx, y + dx/2, m, NOT_PUT);
outtextxy (60 + 4*dx, y + dx/2 + 20, "~ ff0000 = 00ffff");
outtextxy (60 + 4*dx, y + dx/2 + 30, "(cyan)");
refresh ();
pause ();
} // modedemo ()
// -----
void colordemo (void)
{
// show RGB colours
int
stop = 0,
i, x, y,
col1, col2, col3;
message ("setcolor(COLOR(r,g,b)) Demonstration");
mainwindow ();
getviewsettings (&viewport);
x = (viewport.right - viewport.left) / 2 - (256 * 3) / 2;
y = (viewport.bottom - viewport.top) / 2;
while (! stop) {
// assign two RGB components, then vary the third
col1 = random (256);
col2 = random (256);
for (col3 = 0; col3 < 256; col3++) {
setcolor (COLOR (col1, col2, col3));
// draw lines
for (i = 0; i < 3; i++) {
line (x, y - maxy / 3, x, y + maxy / 3);
x++;
}
if (ismouseclick (WM_RBUTTONDOWN)) {
closegraph ();
exit (1);
}
} // for
refresh ();
x = (viewport.right - viewport.left) / 2 - (256 * 3) / 2;
delay (100);
if (ismouseclick (WM_LBUTTONDOWN))
stop = 1;
if (ismouseclick (WM_RBUTTONDOWN)) {
closegraph ();
exit (1);
}
} // while
refresh ();
get_click ();
} // colordemo ()
// -----
void pixeldemo (void)
{
// plot pixels quickly
int
stop = 0,
cnt = 0;
message ("putpixel() Demonstration");
mainwindow ();
while (! stop) {
setcolor (COLOR (random (256), random (256), random (256)));
putpixel (random (maxx), random (maxy), getcolor ());
// or: _putpixel (random (maxx), random (maxy));
cnt++;
// refresh the screen every 5000 pixels plotted
if (0 == cnt % 5000)
refresh ();
if (ismouseclick (WM_LBUTTONDOWN))
stop = 1;
if (ismouseclick (WM_RBUTTONDOWN)) {
closegraph ();
exit (1);
}
} // while
refresh ();
get_click ();
} // pixelslow ()
// -----
void linedemo (void)
{
// draw lines and rectangles
int
stop = 0,
x1, y1, x2, y2,
cnt = 0,
rnd;
message ("line(), rectangle() Demonstration");
mainwindow ();
while (! stop) {
rnd = random (2);
setcolor (COLOR (random (256), random (256), random (256)));
switch (rnd) {
case 0:
// the line is clipped anyway
line (random (maxx), random (maxy),
random (maxx), random (maxy));
break;
case 1:
x1 = random (viewport.right - viewport.left);
y1 = random (viewport.bottom - viewport.top);
x2 = x1 + random (viewport.right - viewport.left) / 4;
y2 = y1 + random (viewport.bottom - viewport.top) / 4;
rectangle (x1, y1, x2, y2);
break;
} // switch
cnt++;
if (0 == cnt % 200)
refresh ();
if (ismouseclick (WM_LBUTTONDOWN))
stop = 1;
if (ismouseclick (WM_RBUTTONDOWN)) {
closegraph ();
exit (1);
}
} // while
refresh ();
get_click ();
} // linedemo ()
// -----
#define MAXPOINTS 25
#define PI_CONV (3.1415926 / 180.0)
void linereldemo (void)
{
// show how to use line styles and relative lines
int
stop = 0,
x, y,
width, height,
radius,
i, j, npoints,
pts_x[MAXPOINTS],
pts_y[MAXPOINTS];
double
angle,
step;
message ("setlinestyle(), moveto(), lineto() Demonstration");
mainwindow ();
width = viewport.right - viewport.left + 1;
height = viewport.bottom - viewport.top + 1;
x = width / 2;
y = height / 2;
radius = height / 2 - 20;
while (! stop) {
// create a polygon, at least 5 sides
npoints = 5 + random (MAXPOINTS - 5 + 1);
if (npoints % 2) // even number of sides
setlinestyle (0, 0, THICK_WIDTH);
else // odd number of sides
setlinestyle (0, 0, NORM_WIDTH);
clearviewport ();
setcolor (BLUE + random (MAXCOLORS - 1));
angle = 0.0;
step = 360.0 / npoints;
// evaluate polygon vertices
for (i= 0; i < npoints; i++) {
pts_x[i] = x + (int)(cos (angle * PI_CONV) * radius);
pts_y[i] = y - (int)(sin (angle * PI_CONV) * radius);
angle += step;
}
circle (x, y, radius );
// draw diagonals
for (i = 0; i < npoints; i++) {
for (j = i; j < npoints; j++) {
moveto (pts_x[i], pts_y[i]);
lineto (pts_x[j], pts_y[j]);
}
}
refresh ();
delay (500);
if (ismouseclick (WM_LBUTTONDOWN))
stop = 1;
if (ismouseclick (WM_RBUTTONDOWN)) {
closegraph ();
exit (1);
}
} // while
refresh ();
setlinestyle (0, 0, NORM_WIDTH);
get_click ();
} // linedemo ()
// -----
void boxdemo (void)
{
// draw filled bars
int
stop = 0,
cnt = 0,
x1, y1, x2, y2;
message ("bar() Demonstration");
mainwindow ();
while (! stop) {
// fill colour
setfillstyle (random (USER_FILL),
COLOR (random (256), random (256), random (256)));
x1 = random (maxx);
y1 = random (maxx);
x2 = x1 + random (maxx / 4);
y2 = y1 + random (maxy / 4);
// outline colour
setcolor (COLOR (random (256), random (256), random (256)));
bar3d (x1, y1, x2, y2, 0, 0); // outlined bars
cnt++;
if (0 == cnt % 200) // refresh every 200 bars
refresh ();
if (ismouseclick (WM_LBUTTONDOWN))
stop = 1;
if (ismouseclick (WM_RBUTTONDOWN)) {
closegraph ();
exit (1);
}
} // while
refresh ();
get_click ();
} // boxdemo ()
// -----
void polygondemo (void)
{
// draw filled polygons
int
stop = 0,
cnt = 0,
i,
numpoints,
poly[32];
message ("fillpoly() Demonstration");
mainwindow ();
while (! stop) {
// fill colour
setfillstyle (random (USER_FILL),
COLOR (random (256), random (256), random (256)));
numpoints = 3 + random (14); // max 16
for (i = 0; i < 2 * numpoints; i += 2) {
poly[i] = random (maxx);
poly[i + 1] = random (maxy);
}
// outline colour
setcolor (COLOR (random (256), random (256), random (256)));
fillpoly (numpoints, poly); // outlined filled polygons
cnt++;
if (0 == cnt % 50) // refresh every 50 polygons
refresh ();
if (ismouseclick (WM_LBUTTONDOWN))
stop = 1;
if (ismouseclick (WM_RBUTTONDOWN)) {
closegraph ();
exit (1);
}
} // while
refresh ();
get_click ();
} // polygondemo ()
// -----
void circledemo (void)
{
// draw arcs and ellipses
int
stop = 0,
r = 100,
cnt = 0,
rnd;
message ("arc(), circle(), ellipse() Demonstration");
mainwindow ();
while (! stop) {
rnd = random (3);
setcolor (COLOR (random (256), random (256), random (256)));
switch (rnd) {
case 0:
arc (random (maxx), random (maxy),
random (360), random (360), random (r));
break;
case 1:
circle (random (maxx), random (maxy), random (r));
break;
case 2:
ellipse (random (maxx), random (maxy),
random (360), random (360),
random (r), random (r));
break;
} // switch
cnt++;
if (0 == cnt % 200)
refresh ();
if (ismouseclick (WM_LBUTTONDOWN))
stop = 1;
if (ismouseclick (WM_RBUTTONDOWN)) {
closegraph ();
exit (1);
}
} // while
refresh ();
get_click ();
} // circledemo ()
// -----
void ellipsedemo (void)
{
// draw filled ellipses
int
stop = 0,
r = 100,
cnt = 0;
message ("fillellipse() Demonstration");
mainwindow ();
while (! stop) {
setfillstyle (random (USER_FILL),
COLOR (random (256), random (256), random (256)));
setcolor (COLOR (random (256), random (256), random (256)));
fillellipse (random (maxx), random (maxy),
random (r), random (r));
cnt++;
if (0 == cnt % 200)
refresh ();
if (ismouseclick (WM_LBUTTONDOWN))
stop = 1;
if (ismouseclick (WM_RBUTTONDOWN)) {
closegraph ();
exit (1);
}
} // while
refresh ();
get_click ();
} // ellipsedemo ()
// -----
int
sierp_x,
sierp_y,
len;
static void sierp_a (int i);
static void sierp_b (int i);
static void sierp_c (int i);
static void sierp_d (int i);
// Sierpinsky curve; taken from Niklaus Wirth's
// Algorithms + Data Structures = Programs
static void sierp_a (int level)
{
if (level > 0) {
sierp_a (level - 1);
sierp_x += len;
sierp_y -= len;
lineto (sierp_x, sierp_y);
sierp_b (level - 1);
sierp_x += 2*len;
lineto (sierp_x, sierp_y);
sierp_d (level - 1);
sierp_x += len;
sierp_y += len;
lineto (sierp_x, sierp_y);
sierp_a (level - 1);
}
}
static void sierp_b (int level)
{
if (level > 0) {
sierp_b(level - 1);
sierp_x -= len;
sierp_y -= len;
lineto (sierp_x, sierp_y);
sierp_c (level - 1);
sierp_y -= 2*len;
lineto (sierp_x, sierp_y);
sierp_a (level - 1);
sierp_x += len;
sierp_y -= len;
lineto (sierp_x, sierp_y);
sierp_b (level - 1);
}
}
static void sierp_c (int level)
{
if (level > 0) {
sierp_c (level - 1);
sierp_x -= len;
sierp_y += len;
lineto (sierp_x, sierp_y);
sierp_d (level - 1);
sierp_x -= 2*len;
lineto (sierp_x, sierp_y);
sierp_b (level - 1);
sierp_x -= len;
sierp_y -= len;
lineto (sierp_x, sierp_y);
sierp_c (level - 1);
}
}
static void sierp_d (int level)
{
if (level > 0) {
sierp_d (level - 1);
sierp_x += len;
sierp_y += len;
lineto (sierp_x, sierp_y);
sierp_a (level - 1);
sierp_y += 2*len;
lineto (sierp_x, sierp_y);
sierp_c (level - 1);
sierp_x -= len;
sierp_y += len;
lineto (sierp_x, sierp_y);
sierp_d (level - 1);
}
}
void sierpinski (int level)
{
sierp_a (level);
sierp_x += len;
sierp_y -= len;
lineto (sierp_x, sierp_y);
sierp_b (level);
sierp_x -= len;
sierp_y -= len;
lineto (sierp_x, sierp_y);
sierp_c (level);
sierp_x -= len;
sierp_y += len;
lineto (sierp_x, sierp_y);
sierp_d (level);
sierp_x += len;
sierp_y += len;
lineto (sierp_x, sierp_y);
}
// -----
void floodfilldemo (void)
{
// show how to use floodfill ()
int
sierp_width,
stop = 0;
message ("floodfill() Demonstration");
mainwindow ();
width = viewport.right - viewport.left + 1;
height = viewport.bottom - viewport.top + 1;
setcolor (WHITE);
// each "petal" is (len*6) pixels wide; at recursion level "N", we have
// 2^(N-1) petals connected by 2^(N-1)-1 segments, which are (2*len)
// pixels long. The overall width of the Sierpinski curve is then:
// W = (len*6)*2^(N-1) + (len*2)*2^(N-1)-1
// For example: given len=5, at recursion level 5 we'll have 16
// petals connected by 15 segments; width = 5*8*16 + 5*2*15 = 630 pixels.
// find max possible length
len = 15;
while ( (sierp_width = len*6*16 + len*2*15) > height - 4)
len--;
sierp_width = (len*6)*16 + (len*2)*15;
sierp_x = width / 2 - sierp_width / 2;
sierp_y = height - (height - sierp_width) / 2;
moveto (sierp_x, sierp_y);
sierpinski (5);
while (! stop) {
setfillstyle (SOLID_FILL, 1 + random (YELLOW));
// center of the Sierpinski curve
floodfill (width / 2, height / 2, WHITE);
refresh ();
delay (100);
setfillstyle (SOLID_FILL, 1 + random (YELLOW));
// outside
floodfill (1, 1, WHITE);
refresh ();
delay (100);
if (ismouseclick (WM_LBUTTONDOWN))
stop = 1;
if (ismouseclick (WM_RBUTTONDOWN)) {
closegraph ();
exit (1);
}
} // while
refresh ();
pause ();
} // floodfilldemo ()
// -----
void alphademo (void)
{
int
stop = 0,
x1, y1, x2, y2;
message ("setalpha() Demonstration");
mainwindow ();
while (! stop) {
setcolor (COLOR (random (256), random (256), random (256)));
setalpha (getcolor (), random (64)); // alpha component of ARGB
setfillstyle (SOLID_FILL, getcolor ());
x1 = random (maxx);
y1 = random (maxx);
x2 = x1 + random (maxx / 4);
y2 = y1 + random (maxy / 4);
bar (x1, y1, x2, y2);
// alpha is applied ONLY when refresh () is called
refresh ();
if (ismouseclick (WM_LBUTTONDOWN))
stop = 1;
if (ismouseclick (WM_RBUTTONDOWN)) {
closegraph ();
exit (1);
}
} // while
refresh ();
get_click ();
} // alphademo ()
// -----
void readimagedemo (void)
{
// load a .bmp file
int
stop = 0,
x, y;
message ("readimagefile() Demonstration");
mainwindow ();
while (! stop) {
// out of the viewport, too
x = random (maxx);
y = random (maxy);
// bitmap is 512x180 px
readimagefile ("logo.bmp", x, y, // position
x + random (512), // size