Render State - Revision history

Redmaw: Added Get Point and Get Object Vector nodes

2025-12-20T01:06:36Z

Added Get Point and Get Object Vector nodes

Matt: Typo fix

2017-11-22T23:19:23Z

Typo fix

Matt: /* Scalars */

2011-05-02T08:17:17Z

‎Scalars

Matt: /* Scalars */

2011-05-02T08:15:43Z

‎Scalars

Matt: /* Scalars */

2011-05-02T08:14:22Z

‎Scalars

Matt: /* Scalars */

2011-05-02T08:12:58Z

‎Scalars

Matt: /* Scalars */

2011-05-02T08:11:09Z

‎Scalars

Matt: /* Scalars */

2011-05-02T08:11:01Z

‎Scalars

Matt: /* Colours */

2011-05-02T07:59:31Z

‎Colours

Matt: /* Overview */

2011-05-02T06:34:41Z

‎Overview

← Older revision		Revision as of 01:06, 20 December 2025
Line 22:		Line 22:

	[[Get Camera Position]] - Position of the main camera in world space, independent of current shading context		[[Get Camera Position]] - Position of the main camera in world space, independent of current shading context
		+
		+	[[Get Object Vector]] - Position, size or direction of object in world space
		+
		+	[[Get Point]] - Position of point in texture, object, or world space

	[[Get Position]] - Position of the point in world space, with displacement		[[Get Position]] - Position of the point in world space, with displacement

@@ Line 41: / Line 41: @@
 === Colours ===
-Some, of all, of the following colour variables may have been set with useful information, depending on what shaders were called prior to executing them.
+Some, or all, of the following colour variables may have been set with useful information, depending on what shaders were called prior to executing them.
 [[Get Diffuse Colour]] - Surface diffuse coefficient, before lighting

@@ Line 13: / Line 13: @@
 === Scalars ===
-[[Get Altitude]] - Signed distance from ''Position in Geometry'' to ''Position'' along the direction of ''Normal in Geometry''
+[[Get Altitude]] - Signed distance from ''Position in Geometry'' to ''Position'' along the direction of ''Normal in Geometry''. For a planet this basically means the altitude of the current point being rendered, including displacement.
 [[Get Altitude in Texture]] - Signed distance from ''Position in Geometry'' to ''Position in Texture'' along the direction of ''Normal in Geometry''. For a planet this basically means the altitude of the current texture coordinates.

@@ Line 15: / Line 15: @@
 [[Get Altitude]] - Signed distance from ''Position in Geometry'' to ''Position'' along the direction of ''Normal in Geometry''
-[[Get Altitude in Texture]] - Signed distance from ''Position in Geometry'' to ''Position in Texture'' along the direction of ''Normal in Geometry''
+[[Get Altitude in Texture]] - Signed distance from ''Position in Geometry'' to ''Position in Texture'' along the direction of ''Normal in Geometry''. For a planet this basically means the altitude of the current texture coordinates.
 [[Get Frame Number]]

@@ Line 13: / Line 13: @@
 === Scalars ===
-[[Get Altitude]] - Signed distance from Position in Geometry to Position along the direction of Normal in Geometry
+[[Get Altitude]] - Signed distance from ''Position in Geometry'' to ''Position'' along the direction of ''Normal in Geometry''
-[[Get Altitude in Texture]]
+[[Get Altitude in Texture]] - Signed distance from ''Position in Geometry'' to ''Position in Texture'' along the direction of ''Normal in Geometry''
 [[Get Frame Number]]

@@ Line 47: / Line 47: @@
 [[Get Emitted Colour]] - Surface emission (luminous) component
-[[Get Final Alpha]] - Surface final output alpha (3-part alpha channel)
+[[Get Final Alpha]] - Surface final output alpha
 [[Get Final Colour]] - Surface final output colour
@@ Line 53: / Line 53: @@
 [[Get Final Opacity]] - Surface final opacity (1 - transparency)
-[[Get Specular Colour]] - Surface specular component (may not be treated consistently between shaders)
+[[Get Specular Colour]] - Surface specular component

@@ Line 1: / Line 1: @@
 == Overview ==
-The Render State is a collection of variables and functions that shaders access and modify during rendering. It is the main point of communication between shaders and the rendering of an image. Whenever a shader is asked to do something, e.g displace a point or tell the renderer what colour a pixel should be, the shader gets information about the point to shade from the Render State. In turn the shader sends information back to the renderer by modifying values in the Render State, and this is how the renderer knows what colour to draw or how far a surface should be displaced at a particular location.
+The Render State is a collection of variables and functions that shaders access and modify during rendering. It is the main point of communication between shaders and the rendering of an image. Whenever a shader is asked to do something, e.g displace a point or tell the renderer what colour a pixel should be, the shader gets information about the point to shade from the Render State. In turn the shader sends information back to the renderer by modifying values in the Render State, and this is how the renderer knows what colour to draw or what shape a surface should be. This is usually done on a point-by-point basis. Roughly speaking, the renderer works on a single pixel or a single micro-polygon at a time, and asks all the shaders to modify that point.
 Some shaders modify the state so that they can change the behaviour of other shaders which are called later. This is how the [[Warp Shader]] can change the shape of other shaders connected to its "Shader" branch, for example.
 Shaders do all this without exposing the details to the user. However, many of the variables in the Render State can be accessed using "Get" function nodes, allowing you to do things that aren't possible with the built-in shaders alone.
 == "Get" Functions ==