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Bram Stout

@stoutnl.bsky.social

Spent the first half of my day setting up a project with an existing build system.

Spent the second half of my day writing my own build system in Python...

Screenshot of the build script run by the custom build system.

Code shown:
import build.build as build

build.Package(
name="...",
version="0.1.0",
dependencies=[
build.Dependency(
packageName="..."
)
]
)

build.addFolder("...")

if __name__ == "__main__":
build.buildAllPackages()

October 10, 2025 at 6:37 AM

Bram Stout

@stoutnl.bsky.social

Also, did you know that MiEx can calculate MC-style ambient occlusion and export it out as an extra vertex colour set? This is EEVEE with just ambient world lighting, no shadows or GI

#minecraft

A screenshot of Blender with a Minecraft world exported from MiEx that shows off the ambient occlusion calculated by MiEx, exported out as a vertex color set, and applied to the diffuse color in the material

June 29, 2025 at 10:35 PM

Bram Stout

@stoutnl.bsky.social

Pizza?

Pizza in pizza oven, almost ready to come out

June 15, 2025 at 7:31 PM

Bram Stout

@stoutnl.bsky.social

I recently went to Scotland for a week and brought my camera with me

I've put the rest of the pictures on my website:
bramstout.nl/en/photograp...

#photography #scotland

Photograph of a hiking trail in Galloway Park, Scotland, in the middle of nature, but with a sign on a tree that says that there are CCTV cameras installed

Picture of Scottish landscape in Galloway Park, near Fort Carrick

Close up of some plants on a stone wall in Mugdock Castle, Scotland

June 8, 2025 at 9:48 AM

Bram Stout

@stoutnl.bsky.social

Been working on further customising Autodesk Maya for
@elementanimation.bsky.social , now with a new launcher!

(Play with sound)

May 29, 2025 at 4:23 PM

Bram Stout

@stoutnl.bsky.social

Cat

Photograph of a cat looking moody, as if he was a detective in a film-noir

May 11, 2025 at 12:12 PM

Bram Stout

@stoutnl.bsky.social

In 2024 @elementanimation.bsky.social switched to using @unrealengine.bsky.social for lighting and rendering. For this, I updated the Element Animation pipeline, which includes an interchange system to get the animations from Maya into Unreal.

Here's a post about it: bramstout.nl/en/work/elem...

Screenshot of some custom Autodesk Maya shelves that are part of the Element Animation pipeline

April 4, 2025 at 3:01 PM

Bram Stout

@stoutnl.bsky.social

I got to work with @elementanimation.bsky.social to do the lighting for "A Wandering Trader Springs to Life!" for #MinecraftLIVE

I also created a new effects system to handle all of the particles and rewrote the Unreal Engine pipeline

I've written about it here: bramstout.nl/en/work/mine...

Thumbnail of the YouTube video "Minecraft LIVE – March 2025: A Wandering Trader Springs to Life!"

March 31, 2025 at 12:42 PM

Bram Stout

@stoutnl.bsky.social

Also my one contribution to the character animation, is adding this singular tear falling from the llama's face

Screenshot from the animation, showing two llamas next to a wandering trader lying on the ground. A tear is falling down from one of the llama's face

March 23, 2025 at 1:36 AM

Bram Stout

@stoutnl.bsky.social

Don't dig straight down.

#minecraft #minecraftart #art #3D #artsky

A CG Minecraft render of a lava pool in a cave, with a shaft of light beaming down onto the lava and items scattered around

March 17, 2025 at 6:14 PM

Bram Stout

@stoutnl.bsky.social

Some more progress on the paint stroke lookdev.

Still need to align the strokes to the surface, work on stability, and add in brush stroke textures.

It's entirely driven by a position pass, from which is spawns surface-stable points which then get rendered to the screen

February 21, 2025 at 9:56 AM

Bram Stout

@stoutnl.bsky.social

... and so rather than forcing everyone to use the same colour rendering anyways, the design philosophy of LOOCS is to provide a small set of base colour renderings, so that artists can pick the one that fits best and tweak it to get the exact look that they need.

A collection of images comparing the colour renderings from different colour management workflows (Khronos PBR Neutral, Agx, and ACES) with the colour renderings from LOOCS.

High quality version of the image available at: https://bramstout.nl/content/LOOCS_Comparison_1.jpg

February 17, 2025 at 12:23 PM

Bram Stout

@stoutnl.bsky.social

All operations work together to provide the final look of Filmic Classic. They provide fundamental characteristics to the colour rendering that give a nice starting point to create your own look. But, those fundamental characteristics aren't always appropriate for every project, ...

Code segment combining all of the different operations together:
res = loocs.gamut.convertToGamut(RGB, loocs.gamut.GAMUT_LOOCSG1, loocs.gamut.GAMUT_LOOCSG2)
res = satClip(res)

res = satVib(res, 1.37, 1.41)

res = satContrast(res, 4.0, 0.9, 4.0)

res = resat(res, 500.0, 1.932, 0.816)

res = desat(res, 500.0, 2.0)

res.r = tonemap(res.r)
res.g = tonemap(res.g)
res.b = tonemap(res.b)

res = satVib(res, 0.971, 0.58)

res = res.clamp(0.0, maxLuminance)

g2Res = Color(res.r, res.g, res.b)
res = loocs.gamut.convertToGamut(res, loocs.gamut.GAMUT_LOOCSG2, loocs.gamut.GAMUT_LOOCSG1)

res = g2SatCurve(res, g2Res)

return res

February 17, 2025 at 12:23 PM

Bram Stout

@stoutnl.bsky.social

So, at the end the colour gets converted back to G1 and their saturation remapped so that fully saturated colours remain fully saturated.

Code segment of the saturation remapping code:
def maxSat(RGB : Color):
# Calculate the RGB colour with saturation set to 100%.
Cmax = RGB.maxComponent()
Cmin = RGB.minComponent()
sat = 0.0
if Cmax > 0.00001:
sat = min(max(1.0 - (Cmin / Cmax), 0.0), 1.0)

if sat < 0.99999:
RGB2 = (RGB - Cmin) / (1.0 - sat)
return RGB2
return Color(RGB.r, RGB.g, RGB.b)

def remapSat(sat, maxSat):
# Remap the saturation so that maxSat maps to an output value of 1.0.
scale = 1.0 - maxSat
m = -20.0
mexp = math.exp(m)

f = (math.exp((sat / maxSat) * -m + m) - mexp) / (1.0 - mexp)

return min(max(sat + f * scale, 0.0), 1.0)

def g2SatCurve(RGB : Color, RGB_G2 : Color) -> Color:
# Calculate the maximum saturation in the G2 gamut.
maxSatRGB = maxSat(RGB_G2)

maxSatRGB = loocs.gamut.convertToGamut(maxSatRGB, loocs.gamut.GAMUT_LOOCSG2, loocs.gamut.GAMUT_LOOCSG1)
# Calculate what the maximum saturation achievable by Filmic Classic is in the G1 gamut.
g2Cmax = maxSatRGB.maxComponent()
g2Cmin = maxSatRGB.minComponent()
g2MaxSat = 1.0
if g2Cmax > 0.00001:
g2MaxSat = min(max(1.0 - (g2Cmin / g2Cmax), 0.0), 1.0)

# Calculate the saturation of the current colour in the G1 gamut.
Cmax = RGB.maxComponent()
Cmin = RGB.minComponent()
sat = 0.0
if Cmax > 0.00001:
sat = min(max(1.0 - (Cmin / Cmax), 0.0), 1.0)

# Remap the saturation.
newSat = remapSat(sat, g2MaxSat)

# Apply the new saturation.
if Cmax > 0.0000001:
RGB /= Cmax

Cmin = RGB.minComponent()
RGB -= Cmin
if Cmin < 0.99999:
RGB /= 1.0 - Cmin

RGB *= newSat
RGB += 1.0 - newSat

RGB *= Cmax

return RGB

February 17, 2025 at 12:23 PM

Bram Stout

@stoutnl.bsky.social

Lastly, Filmic Classic uses the G2 gamut, but the display transform takes in the G1 gamut and maps the full G1 gamut into the display gamut. This would limit how saturated the colours from Filmic Classic can show up once put through the display transform.

Comparison image with and without saturation remapping

February 17, 2025 at 12:23 PM

Bram Stout

@stoutnl.bsky.social

This raised dark saturated colours to be brighter, and also lowered bright saturated colours to help keep their saturation for longer. The contrast is only applied on the maximum value, rather than to each channel. This is to preserve saturation and hue.

Code segment for the saturation driven contrast code:
def satContrast(RGB : Color, gamma, contrast, contrastPivot) -> Color:
Cmax = RGB.maxComponent()
Cmin = RGB.minComponent()
# Calculate the saturation.
sat = 0.0
if Cmax > 0.00001:
sat = min(max(1.0 - (Cmin / Cmax), 0.0), 1.0)

# Calculate by how much to reduce the contrast.
contrastStrength = 1.0 - pow(1.0 - sat, 1.0 / gamma)

contrastStrength *= min(max(Cmax / 0.01, 0.0), 1.0)

contrast2 = contrast * contrastStrength + (1.0 - contrastStrength)

# Apply the contrast. The typical contrast formula found online,
# is a pivoted scale, which comes from photographic film and therefore
# is to be applied in logarithmic space. Often the formula is copied
# without this considuration and thus applied to linear or gamma images
# producing incorrect results. This is the same formula but then converted
# to operate in linear space. This linear version of the contrast operator
# has one benifit over the log version, it's able to keep 0.0 at 0.0.
CmaxNew = pow(Cmax / contrastPivot, contrast2) * contrastPivot

# The contrast is applied on the maximum value of the colour rather than
# each individual channel, so as to not affect saturation or hue.
if Cmax > 0.000001:
RGB *= CmaxNew / Cmax

return RGB

February 17, 2025 at 12:23 PM

Bram Stout

@stoutnl.bsky.social

Something that I noticed in photographic film that I liked, was that saturated colours were both very saturated but also bright, really making them stand out. To achieve that brightening effect for saturated colours, I reduced the contrast based on the saturation but with a very high contrast pivot

Comparison image with and without saturation-based contrast

February 17, 2025 at 12:23 PM

Bram Stout

@stoutnl.bsky.social

I ended up at a technique where I apply a saturation (combo of the typical saturation and normalised gamma operations), then the tone-map, and then a desaturation. The combination of both types of saturation operations gave me more control over how the hues of colours are affected.

Code segment for the saturation operations. It is applied before and after the tone-mapping with different values.
def satVib(RGB : Color, sat, vib) -> Color:
Cmax = RGB.maxComponent()

if Cmax > 0.0000001:
# Apply normalised gamma as a saturation operation.
RGB /= Cmax

RGB.r = pow(RGB.r, vib)
RGB.g = pow(RGB.g, vib)
RGB.b = pow(RGB.b, vib)

RGB *= Cmax

Cmax = RGB.maxComponent()

if Cmax > 0.0000001:
# Apply the typical saturation operation.
# But rather than calculating the new saturation
# by multiplying by some factor, which can cause
# saturation to go above 100%, the new saturation
# is calculated by remapping it using a pow operation.
RGB /= Cmax
Cmin = RGB.minComponent()

RGB -= Cmin
if Cmin < 0.99999:
RGB /= 1.0 - Cmin

oldSat = 1.0 - Cmin
newSat = 1.0 - pow(1.0 - oldSat, sat)

RGB *= newSat
RGB += 1.0 - newSat

RGB *= Cmax

return RGB

February 17, 2025 at 12:23 PM

Bram Stout

@stoutnl.bsky.social

For Filmic Classic, I wanted to create something that produces vibrant images with good colour separation. I wanted saturated colours to remain saturated without less saturated colours looking unnatural.

Comparison image with and without pre/post saturation

February 17, 2025 at 12:23 PM

Bram Stout

@stoutnl.bsky.social

However rather than doing a typical saturation operation, the increase in saturation is handled via a normalised gamma, which increase the saturation but also skews colours towards the primaries, allowing colours to more slowly skew towards the secondaries, creating more separation in the highlights

Code segment for the increase in saturation code:
def resat(RGB : Color, desatMaxValue, resatGamma, resatStrength) -> Color:
# Values copied from the desaturation code.
noDesatAt = math.log10(0.01)
fullDesatAt = math.log10(desatMaxValue)

Cmax = RGB.maxComponent()

if Cmax > 0.0000001:
lCmax = math.log10(Cmax)

# Calculate how much to saturate by based on the maximum value
# in a logarithmic space.
factor = min(max((lCmax - noDesatAt) / (fullDesatAt - noDesatAt), 0.0), 1.0)
factor = math.pow(factor, resatGamma)

factor *= resatStrength

# Apply a normalised gamma operation to saturate the colour.
RGB /= Cmax

RGB.r = pow(RGB.r, 1.0 + factor)
RGB.g = pow(RGB.g, 1.0 + factor)
RGB.b = pow(RGB.b, 1.0 + factor)

RGB *= Cmax

return RGB

February 17, 2025 at 12:23 PM

Bram Stout

@stoutnl.bsky.social

So, before the desaturation gets applied, colours get more saturated first. The two combine together where less saturated colours roughly keep their saturations while very saturated colours get less saturated.

Comparison image with and without resaturation

February 17, 2025 at 12:23 PM

Bram Stout

@stoutnl.bsky.social

This gives me more control over when the colours go to white and also better reduces the amount that their hues get skewed to the secondaries as they get brighter. While this desaturation works for very saturated colours, less saturated colours end up too desaturated in the highlights.

Code segment of the desaturation:
def desat(RGB : Color, desatMaxValue, desatGamma) -> Color:
# The value that the tone-mapper maps to 1.0
tonemapClip = 32.8761
noDesatAt = math.log10(0.01)
# The Cmax value where it should produce pure white.
fullDesatAt = math.log10(desatMaxValue)
# The amount to desaturate a 100% saturated colour to
# produce pure white once run through the tone-mapper.
desatAmount = tonemapClip / max(desatMaxValue, tonemapClip)

Cmax = RGB.maxComponent()

if Cmax > 0.0000001:
lCmax = math.log10(Cmax)

# Calculate how much to desaturate by based on the maximum value
# in a logarithmic space.
factor = min(max((lCmax - noDesatAt) / (fullDesatAt - noDesatAt), 0.0), 1.0)
factor = math.pow(factor, desatGamma)

factor *= desatAmount

# Desaturate the colour.
RGB *= 1.0 - factor
RGB += Cmax * factor

return RGB

February 17, 2025 at 12:23 PM

Bram Stout

@stoutnl.bsky.social

The tone-mapping is done per-channel, which can create undesirable results for very saturated colours. Some colour renderings solve this by applying a constant desaturation, but for Filmic Classic I decided to variably desaturate the colours based on their max value.

Comparison image with and without desaturation

February 17, 2025 at 12:23 PM

Bram Stout

@stoutnl.bsky.social

The curve gets cut off a bit before it goes fully flat to preserve more detail in the highlights and shadows. The highlight section can be moved to change the maximum value for HDR. The shadow section causes the black-point to be raised, so at the end the values get remapped to compensate for that.

Code segment of tone-mapping:
def tonemapLinear(x : float, slope : float, px : float, py : float) -> float:
return slope * (x - px) + py

def sigmoid(x : float, gamma : float) -> float:
"""
A sigmoid curve that as an additional gamma parameter which changes how
quickly it goes to the extremities without changing the slope at (0, 0).
Only the positive side of the sigmoid is usable.
"""
return 1.0 - math.pow(1.0 - (2.0 / (1.0 + math.exp(-2.0 * x / gamma)) - 1.0), gamma)

def tonemapHighlight(x : float, slope : float, scale : float, gamma : float, px : float, py : float) -> float:
return sigmoid((x - px) * slope / scale, gamma) * scale + py

def tonemapShadow(x : float, slope : float, scale : float, gamma : float, px : float, py : float) -> float:
return -sigmoid((-x + px) * slope / scale, gamma) * scale + py

def tonemap(x : float) -> float:
x = max(x, 0.0000001)
x = math.log10(x)

maxLuminanceLog : float = math.log10(maxLuminance)
slope : float = 1.6
middleGrayX : float = math.log10(0.18)
middleGrayY : float = -0.95
highlightX : float = -0.735 + (maxLuminanceLog / slope)
highlightY : float = tonemapLinear(highlightX, slope, middleGrayX, middleGrayY)
shadowX : float = -1.073
shadowY : float = tonemapLinear(shadowX, slope, middleGrayX, middleGrayY)

if x > highlightX:
x = tonemapHighlight(x, slope, 0.94, 10.0, highlightX, highlightY)
elif x > shadowX:
x = tonemapLinear(x, slope, middleGrayX, middleGrayY)
else:
x = tonemapShadow(x, slope, 1.05, 1.0, shadowX, shadowY)

# clamp to the range that we accept.
x = min(max(x, -2.5), maxLuminanceLog)

x = math.pow(10.0, x)

Dmin : float = math.pow(10.0, -2.5)
x -= Dmin
x /= maxLuminance - Dmin
x *= maxLuminance
return x

February 17, 2025 at 12:23 PM

Bram Stout

@stoutnl.bsky.social

Photographic film handles light in a logarithmic way, so for tone-mapping we first get the log of the value, apply the curve, and then the inverse log. The curve is set up in three pieces for full control: a linear section in the middle and two halves of a sigmoid curve on either end.

A diagram of the tone-curve used in LOOCS Filmic Classic.

February 17, 2025 at 12:23 PM

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