Cidr

Cidr (pronounced "Sidr" which stands for "Simple Drawer" or "Simple Drawing") is (supposed to be) a simple header only 2D graphics library which you can use to draw simple stuff (simple geometric shapes such as lines squares etc, bitmaps and other simple stuff). All it requires is a simple pixel color buffer.

Cidr has following features

• Lines (+ anti aliasing)
• Circles (+ anti aliasing)
• Rectangles
• Triangles
• Shaders for all shapes
• Bitmaps
• Triangles with interpolated color
• Textured triangles
• A simple vector library
• stb_image for image loading and saving
• And much more™

Possibly upcoming features

• Splines
• Stroke thickness
• Rounded rectangles

Here is a small demo of what you can already do with Cidr

Building and running the demo

What you'll need:

• A C++17 compatible compiler
• SDL2
• CMake

Debian based:

sudo apt install cmake libsdl2-dev g++

Mac: Install Xcode Command Line Tools, homebrew and then run

brew install sdl2
brew install cmake

Windows: ¯\_(ツ)_/¯

In order to build, type this in your terminal from the Cidr/ direcotry:

$ mkdir build
$ cd build
$ cmake -G "Unix Makefiles" ..
$ make

And then run the demo

$ ./Cidr

The demo has an option for zoom:

./Cidr [zoom]

In order to switch between shaders, you can press the number keys between 1 and 4 (other number keys will disable the shader). The arrow keys allow you to move the source position of the image and the textured triangles. By pressing keys from 5-8 you switch between "OutOfBound" modes and keys 9 and 0 switch between linear and bilinear interpolation. Press t to turn off the text and shift + t to turn it back on.

Usage

Just copy and paste the cidr.hpp file into your project and do this:

#define CIDR_IMPLEMENTATION

in one C++ file to create the implementation before you include the cidr.hpp file.

Sample code

This code creates and saves an image with the text "cidr" drawn on it. The resulting picture is similar to what you see at the top of the readme.

#define CIDR_IMPLEMENTATION
#include "cidr.hpp"

int main(int argc, char** argv) {
	// Create a bitmap to which we want to draw something
	cdr::Bitmap myBitmap{256, 256};
	// Create a rendere and pass the pixels of the just created bitmap to the renderer
	cdr::Renderer myBitmapRenderer{myBitmap.GetData(), myBitmap.GetWidth(), myBitmap.GetHeight()};
	for (uint32_t x = 0; x < 256; x++) {
		for (uint32_t y = 0; y < 256; y++) {
			// Drawing a pixel on the bitmap with some "bit hackry"
			myBitmap.SetRawPixel(
				(y & (x^~y)) >> (~x&~y) | ((y & (x^~y))),
				(x & (x^y) ) >> (~x& y) | ((x & (x^y) )),
				(y & (x^y) ) >> ( x&~y) | ((y & (x^y) )),
				0xff, x, y);
		}
	}

	// Set text style
	myBitmapRenderer.SetTextFont(cdr::Fonts::Raster8x16);
	myBitmapRenderer.SetTextAlignment(cdr::TextAlignment::CC);
	myBitmapRenderer.SetTextSize(4);
	myBitmapRenderer.SetTextShadowColor(cdr::RGB::Black);
	// Drawing text
	myBitmapRenderer.DrawText("Cidr", 132, 128);

	// Save the edited bitmap as "myBitmap.png"
	myBitmap.SaveAs("myBitmap", cdr::Bitmap::Formats::PNG);
	
	return 0;
}

Dependencies

All you need is a compiler that supports C++17.

License

This project is licensed under the MIT License