trying to achieve this look ocean look in houdini ive looked into heightfield and using the noise then a mask by feature then trying to use the mask in the heightfield erode node im yet to get nice results any pointers and suggestions are appreciated.

Hey there Emma!

That ocean picture is super cool! There are different ways to tackle this look. Let me stick to your thought of using Heightfields. You're on the right track with heightfields and masks. Approach it like you're building the ocean layer by layer:

Deep Blue Sea: For the darker blue parts, try using a big, smooth noise pattern in your heightfield. Imagine gentle underwater hills. You can use a "Mask by Height" node to pick out these deeper areas and color them that deep blue.

Shallow Reef Fun: For the lighter, more colorful parts where the coral is, you need lots of little bumps and details! Try using a noise with smaller details (higher frequency). Try using Copernicus for texturing that amazing ocean look. Color the shallow areas with lighter blues, greens, and even some sandy colors.

Blending it nicely: Use smooth transitions! You might need to use a "Blur" node on your masks to make the colors and depths mix together gently.

Making the Coral Pop: For the actual coral shapes, you could try making some simple 3D shapes of coral. Then, use a "Scatter" node to put lots of points on the shallow parts of your heightfield (using a mask to tell it where the shallow parts are). Finally, use "Copy to Points" to put your coral shapes on those points! It all depends on the look you're after and how real you want it to look.

You could incorporate the plane and it's wake into it all but that's an entirely different topic.

Try Different Noises: Houdini has tons of different noise patterns, like "Perlin Noise" or "Voronoi Noise." Experiment to see what looks best to you!

Combine Masks: You can use more than one mask! Maybe one for the deep areas and another for the really shallow, coral parts.
Examine your reference picture closely. See how the colors change and where the details are.
It might take some playing around, but you'll get there! Keep trying different things and have fun with it! I can't wait to see the end result!😊