LightRampAttrib¶
from panda3d.core import LightRampAttrib
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class
LightRampAttrib
¶ Bases:
RenderAttrib
A Light Ramp is any unary operator that takes a rendered pixel as input, and adjusts the brightness of that pixel. For example, gamma correction is a kind of light ramp. So is HDR tone mapping. So is cartoon shading. See the constructors for an explanation of each kind of ramp.
Inheritance diagram
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enum
LightRampMode
¶ -
enumerator
LRT_default
= 0¶
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enumerator
LRT_identity
= 1¶
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enumerator
LRT_single_threshold
= 2¶
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enumerator
LRT_double_threshold
= 3¶
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enumerator
LRT_hdr0
= 4¶
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enumerator
LRT_hdr1
= 5¶
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enumerator
LRT_hdr2
= 6¶
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enumerator
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static
getClassType
() → TypeHandle¶
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getMode
() → LightRampMode¶ Returns the
LightRampAttrib
mode.
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static
makeDefault
() → RenderAttrib¶ Constructs a new
LightRampAttrib
object. This is the standard OpenGL lighting ramp, which clamps the final light total to the 0-1 range.
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static
makeDoubleThreshold
(thresh0: float, lev0: float, thresh1: float, lev1: float) → RenderAttrib¶ Constructs a new
LightRampAttrib
object. This causes the luminance of the diffuse lighting contribution to be quantized using two thresholds:if (original_luminance > threshold1) { luminance = level1; } else if (original_luminance > threshold0) { luminance = level0; } else { luminance = 0.0; }
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static
makeHdr0
() → RenderAttrib¶ Constructs a new
LightRampAttrib
object. This causes an HDR tone mapping operation to be applied.Normally, brightness values greater than 1 cannot be distinguished from each other, causing very brightly lit objects to wash out white and all detail to be erased. HDR tone mapping remaps brightness values in the range 0-infinity into the range (0,1), making it possible to distinguish detail in scenes whose brightness exceeds 1.
However, the monitor has finite contrast. Normally, all of that contrast is used to represent brightnesses in the range 0-1. The HDR0 tone mapping operator ‘steals’ one quarter of that contrast to represent brightnesses in the range 1-infinity.
FINAL_RGB = (RGB^3 + RGB^2 + RGB) / (RGB^3 + RGB^2 + RGB + 1)
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static
makeHdr1
() → RenderAttrib¶ Constructs a new
LightRampAttrib
object. This causes an HDR tone mapping operation to be applied.Normally, brightness values greater than 1 cannot be distinguished from each other, causing very brightly lit objects to wash out white and all detail to be erased. HDR tone mapping remaps brightness values in the range 0-infinity into the range (0,1), making it possible to distinguish detail in scenes whose brightness exceeds 1.
However, the monitor has finite contrast. Normally, all of that contrast is used to represent brightnesses in the range 0-1. The HDR1 tone mapping operator ‘steals’ one third of that contrast to represent brightnesses in the range 1-infinity.
FINAL_RGB = (RGB^2 + RGB) / (RGB^2 + RGB + 1)
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static
makeHdr2
() → RenderAttrib¶ Constructs a new
LightRampAttrib
object. This causes an HDR tone mapping operation to be applied.Normally, brightness values greater than 1 cannot be distinguished from each other, causing very brightly lit objects to wash out white and all detail to be erased. HDR tone mapping remaps brightness values in the range 0-infinity into the range (0,1), making it possible to distinguish detail in scenes whose brightness exceeds 1.
However, the monitor has finite contrast. Normally, all of that contrast is used to represent brightnesses in the range 0-1. The HDR2 tone mapping operator ‘steals’ one half of that contrast to represent brightnesses in the range 1-infinity.
FINAL_RGB = (RGB) / (RGB + 1)
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static
makeIdentity
() → RenderAttrib¶ Constructs a new
LightRampAttrib
object. This differs from the usual OpenGL lighting model in that it does not clamp the final lighting total to (0,1).
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static
makeSingleThreshold
(thresh0: float, lev0: float) → RenderAttrib¶ Constructs a new
LightRampAttrib
object. This causes the luminance of the diffuse lighting contribution to be quantized using a single threshold:if (original_luminance > threshold0) { luminance = level0; } else { luminance = 0.0; }
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property
mode
→ LightRampMode¶ Returns the
LightRampAttrib
mode.
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enum