esc
Type to search across all notes

Vector Graphics

This is a comprehensive user guide that covers two primary workflows for creating vector graphics, along with an introduction to basic Inkscape operations and core SVG concepts.

Create Vector Graphics: Two Main Workflows

There are two main workflows for creating vector graphics, each with its own starting point and use case.

From Bitmap (JPG/PNG) to SVG

This workflow is for when you start with a bitmap—an image composed of pixels. Common bitmap formats include .jpg, .png, .bmp, and .gif.

Concept: A bitmap becomes pixelated when you zoom in. To make it infinitely scalable, you need a process called vectorization or tracing. This process analyzes the shapes and colors in your bitmap and converts them into a vector graphic, which is described by mathematical formulas.

Steps:
  1. Prepare the bitmap: Start with a high-quality .jpg or .png image.
  2. Trace in Inkscape: Open your image in Inkscape and use the Path -> Trace Bitmap function. This tool automatically generates a vector outline by analyzing the colors and contrast in the image.
  3. Save as SVG: Save the traced outline as a Plain SVG file.
  4. Edit in Inkscape: Use Inkscape to perform visual edits on the generated SVG, such as adjusting nodes, colors, and line thickness.
  5. Edit in VS Code (Optional): For more precise control or automation, open the .svg file in a code editor like VS Code to modify the code directly.
Best Practices & Use Cases:

Use Cases: Converting a .jpg company logo to a scalable format, digitizing a hand-drawn sketch, or extracting an object’s outline from a photograph.

Best Practices: Tracing is best for quick prototypes or when you don’t have the original vector file. Since it’s an automated process, some details may not be perfect, requiring manual adjustments afterward.

From Vector Software (Illustrator) to SVG

This workflow is for when you create the artwork from scratch in a professional vector graphics program.

Concept: A vector graphic is composed of geometric objects like points, lines, and curves, all defined by mathematical formulas. This means the image remains perfectly crisp no matter how much you scale it.

Steps:
  1. Create in Illustrator: Use tools like the Pen tool or Shape tools in Adobe Illustrator to design your graphic. The native file format is .ai.
  2. Export to SVG: From Illustrator, choose File -> Export -> Export As… and select the SVG format.
  3. Edit in Inkscape or VS Code: The exported SVG file can be further edited visually in Inkscape or by modifying its code in VS Code.
Best Practices & Use Cases:

Use Cases: Designing a new logo, creating an icon set for a website, or preparing elements for high-quality print materials.

Best Practices: This is the standard workflow for creating professional-grade vector graphics. It guarantees the highest quality from the start, avoiding the complexities and inaccuracies of converting a bitmap.

Basic Inkscape Operations:

Once you have an SVG file, you can perform visual edits in Inkscape.

Resize Document

  • Go to File -> Document Properties.
  • Under “Customize size,” click Resize page to content.

Trace bitmap

Path -> Trace bitmap

Select and Transform Objects

  • Use the Select and transform objects tool (shortcut F1).
  • Click an object to select it. Drag it to move, or click again to access handles for rotation and scaling.

Edit Paths by Nodes

  • Use the Edit paths by nodes tool (shortcut F2).
  • Add a node: Double-click on a path.
  • Delete a node: Select the node and press the Delete key.
  • Break path: Select a node and click the Break path at selected nodes button in the toolbar.
  • Join selected nodes: Select two or more nodes and click the Join selected nodes button in the toolbar.
  • Join nodes: Select two end nodes and click the Join selected endnodes with a new segment button.
  • Delete segment between two non-endpoint nodes.

Draw freehand lines

  • click/hold and draw lines
  • click once and click another position to draw straight line

Fill bounded areas

Show path directions

Inkscape -> Preferences -> Tools -> Node -> Show path direction on outlines

Path Actions

  • Path -> Combine/Break Apart: Combine multiple paths into one object or separate a combined object.
  • Path -> Simplify: Reduce the number of nodes on a path to create a smoother, cleaner outline.
  • Path -> Reverse: Reverse the direction of the selected path.

Inkscape vs. Plain SVG

Inkscape SVG: This is Inkscape’s default save format. It includes extra metadata and layer information specific to Inkscape, which is helpful for future editing within the program.

Plain SVG: A cleaner, more universal format that removes Inkscape’s private data. It’s generally preferred for web use or for sharing with other software because the file size is smaller and the code is cleaner.

Core SVG Concepts

An SVG file is a text file based on XML that you can open and edit in a code editor. Understanding these core concepts gives you more control over your graphics.

Key Tags

  • <svg>: The root element of every SVG file, which defines the canvas size with width and height attributes.
  • <g>: Stands for Group. It’s used to group multiple SVG elements together, allowing you to apply the same properties like fill (color) or transform to the entire group.
  • <path>: One of the most important tags in SVG, used to define the outline of any shape. Its shape is defined by the d attribute, which contains a series of path commands.
    • Path Commands:
      • M/m: Move to, defines the starting point.
      • L/l: Line to, draws a straight line.
      • C/c: Cubic Bezier curve, draws a curved line.
      • Z/z: Close path, draws a straight line back to the starting point to close the shape.
  • <text>: Used to add text to an SVG. You can set properties like font, size, and color.