I’ve messed around with shape keys in blender. I’m thinking of making a 3D game where the more mana/ energy the character has the bigger and rounder it becomes via inflation/expansion/weight gain and as you cast spells or use abilities you shrink down with advantages and disadvantages to all sizes. You can be big and have access to more powers with the mass of a wrecking ball knocking things down and pushing others aside like a sumo but you’re an easy target being as big as a kaiju. With less mana you’re smaller, harder to hit but easily sent flying with less access to spells and abilities.
When using shape keys I found that at a certain point the mesh clips into itself and it becomes tricky to achieve the desired shape and proportions. I want the in game characters to grow into semi spherical sumos. To alleviate this I move the bones apart and maybe scale them a bit in the same fashion that the hulk grows his shoulders are farther apart as they grow.
For example: I might use the inflate tool to expand different parts of the mesh while using a cast modifier with a spherical shape on the center of mass of the model and use the lattice modifier to stretch out the mesh and then I’ll move the spine upwards a bit to add height and I’ll spread the thighs apart to widen the hips and do the same to the shoulders to give the model a bit more reach before adding volume around those areas. Making the character bigger, rounder, and taller without losing the too much reach and articulation of the limbs and thus achieving the proportions of a semi-spherical sumo body.
TLDR: What I’m thinking of is use the shape keys while transforming and scaling the bones at the same time with interpolation to grow the character in real time as you’re collecting items that expand it in a 3D world.
Which game engine is suitable for this?