You need:
[] – 3D assets, in either OBJ or GLTF form
[] – 3D assets dynamically generated in the code
[] – Textures associated with the models
Then you decide:
[] – the illumination for the scene:
[] – which type of direct light? How many ?
[] – Ambient light type?
[] – Any object having emission?
-
These terms might be enclosed in a scene-wide DescriptorSetLayout
-
For each asset
- [] – Define which vertex format it uses
- [] – Select a BRDF approximation and shading technique, and depending on the scene illumination, define the corresponding Vertex / Fragment shader couple
- [] – Decide which texture it requires
- [] – Decide which data sent from the CPP code the shaders need
- The last two point determines the DescriptorSetLayout for the shader couple
You then:
[] – Examine how many different formats have been used by the assets
[] – How many different DescriptorSetLayout are needed
[] – How many different vertex and fragment shaders are needed
- This will also determine how many pipelines are needed
You can then:
[] – Create the Vertex formats
[] – Define the models and load them
[] – Define the texture and load them
[] – Create a DescriptorSetLayout for the scene-wide and pipeline specific uniform
[] – Create the pipelines needed
[] – For each scene-wide DescriptorSetLayout, create the corresponding DescriptorSet instance
[] – Count the required number of:
- DescriptorSets
- UniformBlocks elements of the DescriptorSets
- Texture elements of the DescriptorSets
[] – For each 3D asset, create its specific DescriptorSet according to the corresponding DescriptorSetLayout. Here is where you will define the size of the corresponding uniform, and assign the textures.
[] – In the procedure that populates the command buffer, enter the command to draw all the primitives:
[] – first bind the scene-wide DescriptorSets
[] – for each different pipeline:
- [] - Bind the pipeline
- [] - For each object belonging to that pipeline:
- [] – Bind the corresponding DescriptorSet
- [] – Bind the vertex and index buffers
- [] – call the draw command for the corresponding mesh
- Remember: it is always easier to load all the 3D objects at the beginning, and then “hide” the ones you do not need by either giving them a zero scale, or by moving them far away from the far plane of the camera.
[] – initialize all the variables for the game logic
[] – in the procedure that handles the user interaction:
[] – Read the user input (from the keyboard, the mouse or the Joystick)
[] – update the camera position and direction (if needed), and the corresponding view / projection matrix
[] – update the variable with the position of the objects
[] – determine the new values of the uniform variable and map them
1 - Vertex formats (C++)
| Name | Data structure |
|---|---|
2 - Data structures for Uniform Block Objects (C++)
| Name | Data structure |
|---|---|
3 - Descriptor Set Layouts
| Variable | Binding | Type | Which shader |
|---|---|---|---|
4 - Vertex Descriptors
| Variable | Format (C++) | Location | Type | Usage |
|---|---|---|---|---|
5 - Pipelines
| Variable | Vertex Shader | Fragment Shader | Vertex format (C++) | Vertex descriptor | Set ID | Desriptor set Layout |
|---|---|---|---|---|---|---|
6 - Mesh objects
| Variable | Vertex Format (C++) | Vertex descriptor | Type | Model File |
|---|---|---|---|---|
7 - Textures
| Variable | File | Sampler |
|---|---|---|
8 - Uniform Blocks Objects, C++ sides
| Type | Variable |
|---|---|
9 - Descriptor Sets
| Variable | Descriptor Set Layout | Binding | Type | C++ data structure | Variable with values | Texture |
|---|---|---|---|---|---|---|
10 - Scene Objects
| ID | Pipeline | Mesh | Descriptor Sets |
|---|---|---|---|