ThorVG

ThorVG is a platform independent lightweight standalone C++ library for drawing vector-based shapes and SVG.

Contents

• Building ThorVG
  • Meson Build
• Quick Start
• API Bindings
• Issues or Feature Requests?

Building ThorVG

thorvg supports meson build system.

Meson Build

install meson and ninja if not already installed.

Run meson to configure ThorVG.

meson build

Run ninja to build & install ThorVG.

ninja -C build install

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Quick Start

ThorVG renders vector shapes on a given canvas buffer.

You can initialize ThorVG engine first:

tvg::Initializer::init(tvg::CanvasEngine::Sw, 0);   //engine method, thread count

You can prepare a empty canvas for drawing on it.

static uint32_t buffer[WIDTH * HEIGHT];          //canvas target buffer

auto canvas = tvg::SwCanvas::gen();              //generate a canvas
canvas->target(buffer, WIDTH, WIDTH, HEIGHT);    //stride, w, h

Next you can draw multiple shapes onto the canvas.

auto rect = tvg::Shape::gen();               //generate a round rectangle
rect->appendRect(50, 50, 200, 200, 20, 20);  //round geometry(x, y, w, h, rx, ry)
rect->fill(100, 100, 0, 255);                //round rectangle color (r, g, b, a)
canvas->push(move(rect));                    //push round rectangle drawing command

auto circle = tvg::Shape::gen();             //generate a circle
circle->appendCircle(400, 400, 100, 100);    //circle geometry(cx, cy, radiusW, radiusH)

auto fill = tvg::RadialGradient::gen();      //generate radial gradient for circle fill
fill->radial(400, 400, 150);                 //radial fill info(cx, cy, radius)

tvg::Fill::ColorStop colorStops[2];          //gradient color info
colorStops[0] = {0, 255, 255, 255, 255};     //index, r, g, b, a (1st color value)
colorStops[1] = {1, 0, 0, 0, 255};           //index, r, g, b, a (2nd color value)
fill.colorStops(colorStop, 2);               //set fil with gradient color info

circle->fill(move(fill));                    //circle color
canvas->push(move(circle));                  //push circle drawing command

This code result looks like this.

Or you can draw pathes with dash stroking.

auto path = tvg::Shape::gen();               //generate a path
path->moveTo(199, 34);                       //set sequential path coordinates
path->lineTo(253, 143);
path->lineTo(374, 160);
path->lineTo(287, 244);
path->lineTo(307, 365);
path->lineTo(199, 309);
path->lineTo(97, 365);
path->lineTo(112, 245);
path->lineTo(26, 161);
path->lineTo(146, 143);
path->close();

path->fill(150, 150, 255, 255);              //path color

path->stroke(3);                             //stroke width
path->stroke(0, 0, 255, 255);                //stroke color
path->stroke(tvg::StrokeJoin::Round);        //stroke join style
path->stroke(tvg::StrokeCap::Round);         //stroke cap style

float pattern[2] = {10, 10};
path->stroke(pattern, 2);                    //stroke dash pattern (line, gap)

canvas->push(move(path));                    //push path drawing command

This path drawing result shows like this.

Next, this code snippet shows you how to draw SVG image.

auto picture = tvg::Picture::gen();         //generate a picture
picture->load("tiger.svg");                 //Load SVG file.
canvas->push(move(picture));                //push picture drawing command

And here is the result.

Begin rendering & finish it at a particular time.

canvas->draw();
canvas->sync();

Now you can acquire the rendered image in buffer memory.

Lastly, terminate the engine after usage.

tvg::Initializer::term(tvg::CanvasEngine::Sw);

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API Bindings

Our main development APIs are written in C++ but ThorVG also provides API bindings such as: C.
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Issues or Feature Requests?

For immediate assistant or support please reach us in Gitter