The Outline Generator is a Blender addon designed to streamline the process of creating and managing stylized outlines for your 3D models. This tool is perfect for artists, animators, and designers who want to achieve a "toon," "cel-shaded," or technical drawing look with minimal effort.

At its core, the addon automates the creation of an outline effect by employing a common industry technique: it applies a Solidify modifier with inverted normals and enables backface culling. This is paired with a dedicated, unlit black material to form a clean and customizable border around your objects.

All functionalities are consolidated into a single, convenient panel located in the 3D Viewport's sidebar (View3D > Sidebar > Outline). From this panel, you can:

• Add or remove outlines for selected objects or all objects in the scene with a single click.
• Customize the outline's appearance, including its thickness and color.
• Easily toggle the outline's visibility in both the viewport and the final render.
• Access utility tools to manage materials and selections.

The goal of Outline Generator is to take a multi-step, repetitive manual process and transform it into an efficient, interactive, and user-friendly workflow.

Installing the Render Manager addon follows the standard procedure for any Blender addon.

1. Download the Addon: First, download the latest release of the addon as a .zip file from the marketplace. It is crucial that you DO NOT unzip or extract this file. Blender installs addons directly from the compressed .zip file.
2. Open Blender Preferences: Launch Blender and navigate to the preferences window by selecting Edit > Preferences....
3. Install from File: In the Preferences window, select the Add-ons tab on the left. Click the Install... button located at the top right of the window.
4. Select the .zip File: A file browser will open. Navigate to where you saved the downloaded .zip file, select it, and click the Install Add-on button.
5. Enable the Addon: Blender will install the addon and filter the list to show it. Find "Render: Render Manager" in the list and enable it by ticking the checkbox next to its name.

Once enabled, the Render Manager panel will be available in the Output Properties tab of the Properties editor.

The addon requires no special setup in Blender's Preferences. All settings are located directly in the addon panel.

The Outline Generator panel provides a set of straightforward tools to manage the outline effect on your objects. These tools handle the creation, removal, and visibility of the outlines.

• Add selected outlines: Applies the outline effect to all currently selected mesh objects. If an outline material doesn't exist, it will be created and added to the object along with the necessary "Solidify" modifier.
• Add all outlines: Performs the same action but on every mesh object in the entire scene.
• Remove selected outlines: Reverts the changes on the selected objects by removing the "Outline" modifier and its corresponding material slot.
• Remove all outlines: Performs the same removal operation on every object in the scene that has an outline.
• Fix Outline: This tool is designed to solve a common issue where the outline doesn't appear correctly. It checks the material slots on selected objects and ensures the Outline material is in the last position. The "Solidify" modifier relies on this material order to apply the outline color correctly.
• Select All Outlines: This operator deselects any currently selected objects and then selects every object in the scene that has an outline modifier applied. It's a convenient way to manage all outlined objects at once for tweaking settings.
• Visibility Toggles: These two icon buttons allow you to quickly control the visibility of the outlines on selected objects.
  • Toggle Outline in viewport: Shows or hides the outline effect in the 3D Viewport. This is useful for temporarily disabling the effect to improve performance or reduce visual clutter.
  • Toggle Outline in render: Enables or disables the outline in the final rendered image.

Beyond the main creation tools, the addon provides several settings to fine-tune the appearance of your outlines and control how they are displayed in the viewport.

Outline Settings

Once an outline has been added to an object, a new set of options appears in the panel. These settings allow you to customize the look of the effect.

• Thickness: This value directly controls the thickness of the outline by adjusting the Solidify modifier on the selected objects. Higher values create a bolder line.
• Clamp: This limits the extent of the solidification effect, which can help prevent visual artifacts and spikes on more complex or sharp-edged models.
• Set Thickness / Set Clamp: After entering a new value in the Thickness or Clamp fields, you must press the corresponding "Set" button. This action applies the new value to the outline modifier of all currently selected objects.
• Outline Color: This color picker allows you to change the color of the outline. Since all outlined objects share a single Outline material, changing this color will instantly update the outline on every object using it throughout your scene.

Backface Culling (viewport)

This checkbox is a convenient shortcut to a global Blender viewport setting that is essential for the outline effect to work correctly.

The outline is created by essentially making a slightly larger, inside-out copy of your mesh. Backface Culling tells the viewport to hide the "back side" of 3D faces. When enabled, you can see through the front of the outline mesh to the original model inside, making only its "rim" visible as an outline.

• The addon automatically enables this setting for you when you create the first outline to ensure it's visible.
• You can use this checkbox in the panel to toggle it on or off at any time.

To get the best performance and visual results from the Outline Generator, especially in complex projects, consider the following user-side optimizations.

1. Control Mesh Complexity

The performance of the outline effect is directly tied to the polygon count of your model. The Solidify modifier, which the addon uses to create the outline, has to process every face, edge, and vertex.

• For High-Poly Models: If you experience slowdowns in the viewport on very detailed meshes, the best optimization is to reduce the number of polygons the modifier has to calculate. Consider creating a simplified, lower-polygon version of your model (a "proxy" or "LOD" mesh) specifically for generating the outline.
• General Use: Applying outlines to low-to-medium complexity models will always yield the best performance.

2. Manage Viewport Performance

In scenes with many outlined objects or high-poly models, real-time viewport performance can be affected.

• Toggle Viewport Visibility: The addon provides a dedicated button to toggle the outline's visibility in the viewport. If your viewport becomes slow, simply select the heavy objects and click this button to temporarily disable the outline effect. This will not affect the final render, allowing you to work smoothly without sacrificing the final look.

While the tools are simple, using them in a logical order can significantly speed up your work. Here is a recommended workflow for integrating the Outline Generator into your projects.

1. Test on a Single Object: Start by selecting a single, representative object from your scene. Use the Add selected outlines button to apply the initial effect. This allows you to see the default result without affecting your entire scene.
2. Customize and Refine: With the test object still selected, adjust the Thickness and Outline Color to match your desired art style. Remember to press Set Thickness to apply any changes you make to that property.
3. Apply to All Objects: Once you are happy with the look, you can apply it to the rest of your models. The most efficient way is to use the Select All Outlines button (which will re-select your initial object) and then Shift + Click to add the other desired objects to your selection. Finally, click Add selected outlines once more to apply the effect to the new objects.
4. Manage and Maintain:
   • As your scene grows, use the Toggle Outline in viewport button (the eye icon 👁️) to temporarily hide the outlines if you notice any viewport slowdown.
   • If you add new materials to an object and the outline stops working correctly, select the object and press Fix Outline. This reorders the materials and is a crucial step for maintaining the effect during a long project.
5. Global Removal: If you need to remove all the outlines, simply use the Remove all outlines button to clean up the scene in one click.

This basic, step-by-step tutorial will guide you through the entire process of using the Outline Generator on a simple object. All you need is a new Blender scene.

Step 1: Add the First Outline

• Start with Blender's default scene containing a single Cube.
• Select the Cube.
• In the 3D Viewport, press the N key to open the sidebar if it's hidden.
• Find and click on the "Outline" tab.
• Click the Add selected outlines button. You will immediately see a black outline appear on the cube. The addon automatically enables the necessary Backface Culling viewport setting for you.

Step 2: Customize the Thickness

• With the Cube still selected, look for the Outline Settings section in the addon panel.
• Change the Thickness value from the default of 0.1 to a larger value, such as 0.3.
• Click the Set Thickness button next to the value field. The outline on the cube will become noticeably thicker.

Step 3: Change the Color

• In the same panel, find the Outline Color setting at the bottom.
• Click the color swatch and pick a new color, for example, a bright red.
• The outline's color will update instantly. This happens because all outlined objects share one single, efficient material that the addon creates.

Step 4: Work with Multiple Objects

• Add a new mesh to your scene, like a UV Sphere (Shift + A > Mesh > UV Sphere).
• With the new sphere selected, click Add selected outlines. It will get the same red, thick outline.
• Now, click the Select All Outlines button. Both the cube and the sphere will become selected. This is very useful for managing all outlined objects at once.

Step 5: Remove the Outline

• With both objects still selected, click the Remove selected outlines button.
• The outlines, modifiers, and materials will be cleanly removed from the objects, returning them to their original state.

Congratulations! You have now learned the core workflow of adding, customizing, and managing outlines with the addon.

Q: I clicked "Add selected outlines", but I don't see anything! Why?

A: The most common reason is that Backface Culling is not active in your viewport. This addon's technique relies on this setting to make the outline visible.

• Solution: In the addon panel, ensure the checkbox labeled "Backface Culling (viewport)" is checked. The addon enables it automatically when you add the first outline, but it might have been disabled afterward.

Q: The outline on my object has the wrong color or seems to be using another material. How can I fix this?

A: This usually happens when the Outline material is not in the last material slot on your object. The addon's modifier is set to apply the last material in the stack as the outline color. If you add new materials after creating the outline, the order can get mixed up.

• Solution: Select the object that has the issue and click the "Fix Outline" button in the addon panel. This will automatically move the Outline material to the last slot for you.

Q: I changed the value in the "Thickness" or "Clamp" field, but nothing happened to my model.

A: Just changing the value in the number field does not automatically apply it. You must explicitly tell the addon to send that new value to the selected objects' modifiers.

• Solution: After typing your new value, you must click the "Set Thickness" or "Set Clamp" button next to the field to apply the change.

Q: My outline looks strange, with big spikes coming off the corners. How do I make it cleaner?

A: This is a common artifact of the underlying Solidify modifier, especially on sharp angles. The addon includes a feature to control this.

• Solution: Use the Clamp property in the "Outline Settings" section. Start with a small value (e.g., 1.0) and click the "Set Clamp" button. This will limit the "overshooting" of the outline, resulting in a much cleaner and more controlled look.

Q: I want different objects to have different colored outlines, but when I change the color, it changes everywhere. Is this possible?

A: Yes, but it requires a quick manual step. By default, the addon uses one shared material for all outlines to save memory and improve performance. To assign a unique color, you need to create a unique copy of this material.

• Solution:
  1. Select the object you want to have a unique color.
  2. Go to the Material Properties tab in Blender's Properties Editor.
  3. You will see the Outline material assigned. Click the "New material" icon (it looks like two pages, often with a number next to it indicating how many objects use it). This will create a single-user copy (e.g., Outline.001).
  4. You can now change the color of this new material without affecting the others.

Q: Why can't I add an outline to a Curve, Light, or Camera?

A: The addon is designed to work exclusively with Mesh objects. The underlying technique uses a Solidify modifier, which can only operate on mesh geometry.

If you believe you have found a bug or are experiencing an issue not covered in this documentation, we encourage you to report it. Your feedback is essential for improving the addon for everyone.

Please use the official contact method or support ticket system on the marketplace where you purchased the product (e.g., Blender Market, Gumroad, etc.).

What to Include in Your Bug Report

To help us resolve the issue as quickly as possible, please include the following information in your report:

• Addon Version: The version of the addon you are using (e.g., 1.5.0).
• Blender Version: The version of Blender you are using (e.g., 4.1, 3.6 LTS).
• Operating System: Your operating system (e.g., Windows 11, macOS Sonoma, Linux).
• A Clear Description of the Problem: Please describe what happened and what you expected to happen.
• Steps to Reproduce: A numbered list of the exact steps needed to trigger the bug. This is the most important part of the report.
• Error Messages: If any error messages appear, please open Blender's System Console (Window > Toggle System Console) and copy and paste the entire message into your report.
• Sample .blend File (Optional but very helpful): If possible, attaching a simple .blend file that demonstrates the issue is the best way for us to quickly identify and fix the problem.

Thank you for taking the time to submit a report. We appreciate your help in making our tools better!