add Mergemaps RGBA HDA

README.md

@@ -6,11 +6,20 @@ Not much here yet...
 
 ## /hda - digital assets
 
+### Merge maps RGB
+
+Allows merging of up to 3 images into a single color attrib (one image per
+channel). Each channel provides the same customization options as "Attrib from
+Map" SOP.
+
 ### PTF (Parallel Transport Frames)
 
 <small>Tags: VEX, curves, polygons</small>
 
-Sweeps profile shape along one or multiple curves. Use multiple instances for recursive application. Parameters for twisting, radius modulation ramp, multiple generation modes: curves, tube, disc. Includes Help page w/ further details.
+Sweeps profile shape along one or multiple curves. Use multiple instances for
+recursive application. Parameters for twisting, radius modulation ramp,
+multiple generation modes: curves, tube, disc. Includes Help page w/ further
+details.
 
 ### Phyllotaxis
 
@@ -22,13 +31,15 @@ Point generator for phyllotaxis patterns
 
 <small>Tags: Python, polygons</small>
 
-Imports first `<polygon>` element from given SVG file. No SVG transforms are supported. No 3rd party deps required.
+Imports first `<polygon>` element from given SVG file. No SVG transforms are
+supported. No 3rd party deps required.
 
 ### Tessellations
 
 <small>Tags: Python, polygons</small>
 
-Recursive face tessellations: tri fan, quad fan, edge split triangles. An optional displacement amount can be specified for the latter two modes.
+Recursive face tessellations: tri fan, quad fan, edge split triangles. An
+optional displacement amount can be specified for the latter two modes.
 
 ## /hip - scenes
 
@@ -38,15 +49,22 @@ Recursive face tessellations: tri fan, quad fan, edge split triangles. An option
 
 ![](assets/dejong.jpg)
 
-Uses an OpenCL kernel to compute the 2D DeJong strange attractor w/ 3 million particles, then applies a second kernel to perform stereographic transformation to 3D.
+Uses an OpenCL kernel to compute the 2D DeJong strange attractor w/ 3 million
+particles, then applies a second kernel to perform stereographic transformation
+to 3D.
 
 ### DLA
 
 <small>Tags: VEX, simulation, points</small>
 
 ![](assets/dla.jpg)
 
-VEX simulation of Diffusion-limited aggregation (DLA), supports various params to control growth. Sim uses an initial set of seed particles, then each frame spawns a fixed number of new particles in the vicinity of existing points. Each particle has a selection probability attrib, which decays each time the particle is used as growth source. Once that probability is less than configured threshold the particle is ignored as source for new growth.
+VEX simulation of Diffusion-limited aggregation (DLA), supports various params
+to control growth. Sim uses an initial set of seed particles, then each frame
+spawns a fixed number of new particles in the vicinity of existing points. Each
+particle has a selection probability attrib, which decays each time the
+particle is used as growth source. Once that probability is less than
+configured threshold the particle is ignored as source for new growth.
 
 This implementation is based on the approach taken in [toxiclibs](http://toxiclibs.org/2010/02/new-package-simutils/). For an alternative approach, see [Entagma](http://www.entagma.com/vex-in-houdini-diffusion-limited-aggregation-plus-rendering-in-mantra-redshift/).
 
@@ -56,8 +74,12 @@ This implementation is based on the approach taken in [toxiclibs](http://toxicli
 
 ![](assets/dipoles.jpg)
 
-VEX field line simulation between randomly charged dipoles. Takes an input geometry, and spawns a configurable number of agents in a disc around each point. These agents are then attracted/repelled by other poles in the field. Each agent's trajectory is stored in individual polylines. Agents are removed from the sim (not updated further) once they've reached another pole.
+VEX field line simulation between randomly charged dipoles. Takes an input
+geometry, and spawns a configurable number of agents in a disc around each
+point. These agents are then attracted/repelled by other poles in the field.
+Each agent's trajectory is stored in individual polylines. Agents are removed
+from the sim (not updated further) once they've reached another pole.
 
 ## License
 
-&copy; 2017 Karsten Schmidt // ASL2 licensed
+&copy; 2017 - 2018 Karsten Schmidt // ASL2 licensed