3D modeling process is a multi-step process that brings characters, objects, and environments to life. From video games to animations, the quality of the final 3D model depends heavily on the care and technical finesse applied across numerous modeling stages. The process begins with gathering visual references and ends with the final rendering. In this article, we will provide key insights into the craft behind 3D modeling. It also outlines the necessary steps modelers take to balance visual quality with practical runtime considerations.
1. Concept and Reference Gathering
In order to define the vision and purpose of the 3D model, we need concept art services. This stage allows us to define the parameters like art style, level of realism, materials, etc. With an early guideline from concept artists, we can set our 3D modeling workflow and set clear goals. Model sheets are delivered after the final concept for a better modeling guideline.
Having relevant references is critical. For character modeling, anatomical references ensure proper body proportions. For environments, collecting architectural plans or maps of actual places provides modeling dimensions. They help modelers develop an intuitive sense of natural shapes and forms.
In the blockout stage, we use simple shapes rather than nitty-gritty details to define the major mass distribution, silhouettes, proportions, and overall scale. For example, a character blockout will show the head size relative to the body, limb lengths, etc. This stage allows us to quickly iterate over layout concepts before investing effort into details. In blockout, standard primitive shapes like cubes, spheres, and cylinders are commonly used in order to make adding finer details much easier in subsequent modeling stages.
3. Basic Model Shape
The basic model shape stage bridges the gap between blockout and final surface modeling. More defined forms and proportions are established but keeping surfaces simple at first. Basic anatomical landmarks are laid out for characters based on references. This includes the skull, rib cage, hip bones, and limb proportions. For hard surface modeling, changes in surface direction and major functional sub-parts are blocked.
This stage allows evaluating silhouettes and proportions from primary viewing angles without over-committing time to a particular pose. For vehicles or buildings, the major grouped components are created to assess overall balance.
4. Low-Poly Modeling
The low polygon modeling stage creates a base mesh optimized for animation and posing. Edge flow is cleaned up to deform well when articulated. Key areas needing more deformation, such as joints and areas around morph targets, have increased mesh density. Regions needing less detail are reduced in complexity. Triangles and n-gons are converted to quads. Mesh topology is organized, so subsurface smoothing modifiers give good results. Poly count budgets optimized for target hardware platforms are maintained from the start. Careful low poly modeling enhances efficiency for downstream sculpting, texture baking, and rigging stages. This 3D modeling technique balances maximizing geometry usage against animation requirements.
5. UV Mapping
UV mapping is the process of projecting 3D mesh geometry onto a 2D texture space, and it bridges important connections between 3D geometry and 2D painting workflows through different 3D modeling software. It defines how 2D texture maps will be mapped onto the 3D asset.
For organic models, the UV shells are carefully laid out to maximize space for painting complex materials later. Mirroring UVs reduces painting work for symmetric body parts. For hard surface models, UV shells match logical surface regions and repetitions. This makes painting less cumbersome by avoiding disjointed texture spaces.
The 3D sculpting stage adds high-frequency surface details, skin textures, and finer shapes to the underlying base model. Specialized digital sculpting tools displace and build up millions of micro-polygons upon the lower-resolution model. Combining specialized brushes, alphas, and positioning methods mimics real-world sculpting workflows.
This high polygon stage pushes forms, shapes, and personalities to their final state before optimizing topology and baking assembled details down to lower-resolution game assets.
Read More: 3D Modeling vs. Sculpting
Retopology refers to the process of rebuilding a clean quad-based mesh on top of a high-resolution sculpt. While sculpts capture extremely nuanced details, the resulting geometry is often uneven and too dense for animation. Retopology generates an optimized base mesh to receive the baked normal/ambient occlusion details from the sculpt. The goal of this stage is to create the most efficient quad layout to deform predictably when posed and animated while retaining sculpted high-frequency elements on displacement and normal maps.
8. Baking High-Poly to Low-Poly
Baking is the process of transferring surface detail from a high polygon sculpt model onto an optimized low polygon game or animation asset. Details encoded in normal, ambient occlusion or height maps retain all the high-res sculpt information without the heavy memory costs. The low polygon model shares an identical topology and orientation as the sculpted version and sits precisely over it. Special baking tools calculate lighting shading differentials between the low and high models to store as texture maps. Baking retains 100% of painstaking sculpting work as reusable runtime textures.
3D texturing refers to the process of applying 2D bitmap images, referred to as texture maps, to the surface of 3D assets. Textures define the diffuse color, patterns, roughness, normals, and other surface qualities. The textures are painted to match the required material properties and realistic goals. Texturing focuses on both pixel level precision as well as interactive flexibility for downstream users. Advanced tools enable direct texture painting in world space for precise wear based on actual geometry contact.
10. Rendering in 3D Modeling Process
The rendering process generates 2D pixel images from the textures, lighting, and materials defined for 3D scenes and assets. Highly complex software simulations approximate the behavior of light in the real world based on physics models. Light transport calculations determine the visibility, reflection, refraction, and scattering of light rays as they interact with different surfaces. The rendering process brings together all built and configured visual elements in a scene and uses unbiased physics based simulation to generate photorealistic images matching real camera behavior.
Each stage of the process makes important tradeoffs between visual quality, functionality, and performance. Modelers have to work smart to retain high geometric and texture details from sculpts without overloading game engines. UV layouts created early in modeling connect the 3D and 2D stages down the pipeline. Retopology redistributes the mesh based on animation, deformation, and runtime considerations. With so many interdependent steps, clear communication and iteration are crucial to aligning artistic goals with practical constraints.