#Have you ever got intimidated when trying to modify details of a complex model after finishing the whole design or based on files from third parties? With Direct Edit in ZW3D, modifying models can no longer be your trouble. Let’s see how. Traditionally, 3D design is done with parametric modeling, which makes all the model data fully-constrained and synchronized, to meet requirements of industrial production. However, everything has its pros and cons. In parametric modeling mode, modifying a complex model with hundreds of features and constraint relationships could be a huge challenge. For example, if you want to modify a filet of a part in a model, you need to find the part and its features in the history tree, which can be more annoying if the model is complicated with a long history. Moreover, to modify a model, you need to have an overall understanding of how the model was built. Otherwise, you will probably break the model when doing the modifications. So it is even more challenging for those who get used to 2D CAD without experience in parametric design, and those who are not the creators of the models. To solve these problems, the idea of history-free modeling was born, and as a type of this technology, Direct Edit function is also available in ZW3D, enabling you to directly post-edit the model data, instead of editing the features in the history tree. Now, let’s go straight to the key highlights of Direct Edit in ZW3D. 1. History-free post-editing No matter the model is from other CAD systems or created in ZW3D, no matter it has a history or not, and no matter you want to modify or create geometry on the model, you don't need to care about the model building process. Direct Edit supports you to directly edit existing 3D models very flexibly.

Figure 1. Directly edit models no matter they have history or not

2. Maintain original constraint relationships

When you modify a model, ZW3D will automatically identify and maintain its existing constraint relationships regardless of whether it has a history of not. For example, the model below does not have a history. When moving the inner hole, its concentric constraint with the outer circle can be automatically identified, so that the outer circle can be moved with it together.

Figure 2. Maintain the original constraint relationships of the model when modifying

3. Generate new history tree

New history tree will be generated when modifications are added, offering precise engineering data to you to adjust again in parametric mode. Though some mainstream CAD solutions offer Direct Edit functions, ZW3D exclusively retain your modifying process for you. In this way, you could re-edit your modifications via Direct Edit or history tree.

Figure 3. The newly-generated history tree after Direct Edit

4. Edit model dynamically and intuitively

ZW3D’s Direct Edit offers two ways to modify the features. You can input values in the dialog or directly drag the geometry to acquire the results you need. While you are editing the model, the modifications and relevant constraints will be updated in real-time so that you can preview how you are going to change the model dynamically and intuitively.

Figure 4. Dynamically and intuitively modify the model

5. Diversified editing tools with precise control of dimensions Direct Edit offers multiple editing tools with precise control of dimensions. You can choose different commands to modify your models, such as DE Move, Align Move Face, Dim Move Face, etc. Moreover, you can enter an exact value in each operation to control your geometric data. In this way, you can flexibly edit models and at the same time ensure the preciseness of modeling.

Figure 5. Different commands of Direct Edit

Figure 6. Precisely control dimensions when using Direct Edit

To summarize, Direct Edit is your ideal helper in complex product design or in team collaboration, which allows you to deal with geometric models more intuitively and flexibly under a complex history or even without a history. What’s more, the combination of parametric modeling and direct editing in ZW3D offers you more flexibilities in post-editing with the bottlenecks of parametric design settled, while at the same time keeps strictness of modeling. Can’t help to try Direct Edit? Here is a tutorial about modifying a pedestal for you. Grasp this useful tool right away!