Bloom and tonemapping fixes

[tychedelia]

Bloom was enabled by default in Python and was also inserting a tonemapper by default.

We want to make users choose tonemapping explicitly as opt-in, as any kind of tonemapper will shift colors from what they may have written on the CPU (i.e. breaking pixel readback).

[github-actions]

Visual regression: 25 changed of 43 cases

case	status	detail
rectangle	❌ changed	99.96% of pixels differ
py_animated_mesh	❌ changed	99.83% of pixels differ
py_background_image	❌ changed	100% of pixels differ
py_box	❌ changed	99.63% of pixels differ
py_curves	❌ changed	99.69% of pixels differ
py_feedback	❌ changed	1.47% of pixels differ
py_flocking	❌ changed	1.48% of pixels differ
py_geometry_methods	❌ changed	99.87% of pixels differ
py_gltf_load	❌ changed	1.56% of pixels differ
py_lights	❌ changed	92.37% of pixels differ
py_materials	❌ changed	1.09% of pixels differ
py_multi_window	❌ changed	2.16% of pixels differ
py_particles_gpu_surface	❌ changed	17.33% of pixels differ
py_particles_gpu_surface_lit	❌ changed	16.43% of pixels differ
py_particles_lines	❌ changed	2.88% of pixels differ
py_particles_lissajous	❌ changed	98.31% of pixels differ
py_particles_points	❌ changed	24.02% of pixels differ
py_particles_sphere	❌ changed	18.56% of pixels differ
py_particles_surface	❌ changed	16.24% of pixels differ
py_primitives_2d	❌ changed	97.84% of pixels differ
py_rectangle	❌ changed	99.92% of pixels differ
py_shapes	❌ changed	99.62% of pixels differ
py_style_stack	❌ changed	99.64% of pixels differ
py_text	❌ changed	14.64% of pixels differ
py_window_controls	❌ changed	24.1% of pixels differ

Changes accepted by the deliberate-rendering-change label.

_{baseline ad938a8bdd · adapter llvmpipe (LLVM 20.1.2, 256 bits) (Vulkan, Mesa 25.2.8-0ubuntu0.24.04.2 (LLVM 20.1.2))}

Open the visual report · workflow run