Panda3D SimplePBR

Common errors

• AttributeError: module 'simplepbr' has no attribute 'get_shader'

  cause Attempting to call `simplepbr.get_shader()` in SimplePBR versions 0.12.0 or newer.
  fix Remove the call to `get_shader()`. Instead, call `simplepbr.init()` once after initializing `ShowBase`. SimplePBR will automatically apply its shader to `base.render`.

• TypeError: 'NodePath' object is not callable

  cause This often occurs if `simplepbr.init()` is called before the Panda3D `ShowBase` instance (usually `base`) is fully set up, or if `base` is not accessible.
  fix Ensure `base = ShowBase()` is executed and `base` is in scope before calling `simplepbr.init()`.

• Shader compilation error: GLSL: '...' : undeclared identifier

  cause A generic shader error indicating an issue with the GLSL code. This can be due to an outdated Panda3D version, unsupported graphics drivers, or incorrect shader inputs.
  fix Update your Panda3D installation (`pip install --upgrade panda3d`). Ensure your graphics drivers are up to date. Verify that any custom `setShaderInput` calls use the correct input names as expected by SimplePBR (refer to documentation for specific versions).

• KeyError: 'metallic_map' (or 'roughness_map', 'normal_map', etc.)

  cause You are using old shader input names (snake_case) with SimplePBR versions 0.8.0 or newer, which expect camelCase input names.
  fix Change the shader input names from snake_case to camelCase. For example, `setShaderInput('metallic_map', texture)` should become `setShaderInput('metallicMap', texture)`.

Warnings

• breaking The `simplepbr.get_shader()` function was removed. The shader is now applied globally to `base.render` by `simplepbr.init()`.
  Fix: Replace `shader = simplepbr.get_shader()` followed by `np.setShader(shader)` with a single call to `simplepbr.init()` after `ShowBase` is initialized. Shader inputs should now be set on the `NodePath`s directly or `base.render`.
• breaking Shader input names for PBR textures changed from snake_case to camelCase (e.g., `metallic_map` became `metallicMap`).
  Fix: Update any custom `NodePath.setShaderInput()` calls to use the new camelCase naming convention for PBR texture inputs (e.g., `np.setShaderInput('metallicMap', texture)`).
• gotcha SimplePBR requires Python 3.9 or newer and Panda3D 1.10.13 or newer. Using older versions will lead to installation errors or runtime issues.
  Fix: Ensure your Python environment is `Python >= 3.9` and your Panda3D installation is `Panda3D >= 1.10.13`. Upgrade Panda3D with `pip install --upgrade panda3d` if necessary.
• gotcha Applying other shaders to `base.render` or its ancestors after `simplepbr.init()` can lead to conflicts or unexpected rendering results, as SimplePBR sets a global shader.
  Fix: If you need to apply different shaders to specific objects, apply them directly to those objects' `NodePath`s rather than to `base.render`. For global post-processing effects, consider using Panda3D's post-processing framework or integrating it carefully with SimplePBR's setup.

Install

• pip install panda3d-simplepbr Install stable release

Imports

• simplepbr
  wrong:

  from panda3d.simplepbr import init

  correct:

  import simplepbr

  simplepbr is a top-level package, not part of panda3d's namespace.
• init
  wrong:

  from simplepbr import create_simplepbr

  correct:

  simplepbr.init()

  `create_simplepbr` was an older function name; `init()` is the current and recommended entry point.

Quickstart

This quickstart initializes a basic Panda3D scene, loads a default model, and then enables SimplePBR with `simplepbr.init()`. It also sets up minimal lighting required for PBR to function, demonstrating how SimplePBR integrates seamlessly with Panda3D's existing lighting system.

from direct.showbase.ShowBase import ShowBase
from panda3d.core import DirectionalLight, AmbientLight, VBase4
import simplepbr

# Standard Panda3D ShowBase setup
base = ShowBase()
base.camLens.setNearFar(0.1, 1000.0)

# Initialize SimplePBR - this is the core step
simplepbr.init()

# Load a test model (Panda3D's default smiley)
smiley = base.loader.loadModel('smiley')
smiley.reparentTo(base.render)
smiley.setPos(0, 5, 0)
smiley.setHpr(0, 90, 0)

# Add a directional light
dlight = DirectionalLight('dlight')
dlight.setColor(VBase4(0.8, 0.8, 0.8, 1))
dlnp = base.render.attachNewNode(dlight)
dlnp.setHpr(0, -60, 0)
base.render.setLight(dlnp)

# Add some ambient light
alight = AmbientLight('alight')
alight.setColor(VBase4(0.2, 0.2, 0.2, 1))
alnp = base.render.attachNewNode(alight)
base.render.setLight(alnp)

base.run()