simplegfx.c File Reference

Implementation of the simple graphics library. More...

#include "simplegfx.h"
#include <string.h>
#include <windows.h>

Functions
void	gfx_circle (int cx, int cy, int r)
	Draw a circle outline. More...
void	gfx_clear ()
	Clear the entire graphics window to white. More...
void	gfx_close ()
	Close the graphics window and free resources. More...
void	gfx_delay (int ms)
	Pause program execution for specified milliseconds. More...
void	gfx_drawtext (int x, int y, const char *text)
	Draw text at the specified position. More...
int	gfx_init (int w, int h)
	Initialize the graphics window with specified dimensions. More...
void	gfx_line (int x1, int y1, int x2, int y2)
	Draw a line between two points. More...
void	gfx_present ()
	Display all drawn graphics on the screen. More...
void	gfx_putpixel (int x, int y)
	Draw a single black pixel at the specified coordinates. More...
void	gfx_putpixel_color (int x, int y, unsigned char r, unsigned char g, unsigned char b)
	Draw a single pixel with custom RGB color. More...
void	gfx_rect (int x, int y, int w, int h)
	Draw a rectangle outline. More...
static LRESULT CALLBACK	WndProc (HWND h, UINT m, WPARAM w, LPARAM l)

Variables
static HBITMAP	backBmp
static HDC	backDC
static HWND	hwnd
static int	winH
static int	winW

Detailed Description

Implementation of the simple graphics library.

Author

Sukesh Ashok Kumar

Cross-platform graphics implementation:

• Windows: Uses GDI (Graphics Device Interface) with double buffering
• Linux: Uses X11 with optimized TrueColor pixel operations

The library automatically compiles the correct version based on platform.

Function Documentation

gfx_circle()

void gfx_circle	(	int	cx,
		int	cy,
		int	r
	)

Draw a circle outline.

Draws only the border of a circle, not filled.

Parameters

cx	X-coordinate of the circle center
cy	Y-coordinate of the circle center
r	Radius of the circle in pixels

gfx_circle(320, 240, 100); // Circle at center with radius 100

gfx_clear()

void gfx_clear

(

)

Clear the entire graphics window to white.

Erases everything on the screen and fills it with white color.

gfx_close()

void gfx_close

(

)

Close the graphics window and free resources.

Call this before your program exits to properly clean up. Should be the last graphics function you call.

gfx_close();
return 0;

gfx_delay()

void gfx_delay

(

int

ms

)

Pause program execution for specified milliseconds.

Useful for keeping the window open or creating animations.

Parameters

ms	Delay duration in milliseconds (1000 ms = 1 second)

gfx_delay(3000); // Wait 3 seconds

gfx_drawtext()

void gfx_drawtext	(	int	x,
		int	y,
		const char *	text
	)

Draw text at the specified position.

Renders text using the default system font in black color.

Parameters

x	X-coordinate where text starts
y	Y-coordinate of the text baseline
text	The null-terminated string to draw

gfx_drawtext(50, 50, "Hello, World!");

gfx_init()

int gfx_init	(	int	width,
		int	height
	)

Initialize the graphics window with specified dimensions.

Creates a graphics window where you can draw shapes and pixels. Must be called before any other graphics functions.

Parameters

width	Window width in pixels
height	Window height in pixels

Returns

0 on success, -1 on failure (display unavailable, etc.)

if (gfx_init(640, 480) != 0) {
    return 1; // Failed to create window
}

gfx_line()

void gfx_line	(	int	x1,
		int	y1,
		int	x2,
		int	y2
	)

Draw a line between two points.

Draws a straight line connecting point (x1, y1) to point (x2, y2).

Parameters

x1	X-coordinate of the start point
y1	Y-coordinate of the start point
x2	X-coordinate of the end point
y2	Y-coordinate of the end point

gfx_line(0, 0, 100, 100); // Diagonal line

gfx_present()

void gfx_present

(

)

Display all drawn graphics on the screen.

Call this after drawing operations to make them visible. This updates the window with everything you've drawn since the last present.

gfx_circle(100, 100, 50);
gfx_present(); // Now the circle appears on screen

gfx_putpixel()

void gfx_putpixel	(	int	x,
		int	y
	)

Draw a single black pixel at the specified coordinates.

Parameters

x	X-coordinate of the pixel (0 = left edge)
y	Y-coordinate of the pixel (0 = top edge)

gfx_putpixel(100, 50); // Draw black pixel at (100, 50)

gfx_putpixel_color()

void gfx_putpixel_color	(	int	x,
		int	y,
		unsigned char	r,
		unsigned char	g,
		unsigned char	b
	)

Draw a single pixel with custom RGB color.

Allows you to specify any color using Red, Green, Blue components. Each component ranges from 0 (none) to 255 (full intensity).

Parameters

x	X-coordinate of the pixel
y	Y-coordinate of the pixel
r	Red component (0-255)
g	Green component (0-255)
b	Blue component (0-255)

gfx_putpixel_color(100, 50, 255, 0, 0);    // Red pixel
gfx_putpixel_color(100, 51, 0, 255, 0);    // Green pixel
gfx_putpixel_color(100, 52, 0, 0, 255);    // Blue pixel

gfx_rect()

void gfx_rect	(	int	x,
		int	y,
		int	w,
		int	h
	)

Draw a rectangle outline.

Draws only the border of a rectangle, not filled.

Parameters

x	X-coordinate of the top-left corner
y	Y-coordinate of the top-left corner
w	Width of the rectangle in pixels
h	Height of the rectangle in pixels

gfx_rect(50, 50, 200, 100); // 200x100 rectangle at (50, 50)

WndProc()

static LRESULT CALLBACK WndProc ( HWND  h, UINT  m, WPARAM  w, LPARAM  l  )

static

Variable Documentation

backBmp

HBITMAP backBmp

static

backDC

HDC backDC

static

hwnd

HWND hwnd

static

winH

int winH

static

winW

int winW

static