I've also had a stab at a high-res version of the icon for when this finally goes up on Google Play

It's been a while so I thought I'd do a quick update. I've added a lot of the game functionality now. I have stacks of blocks that will collapse if you hit them. They are stacked in a hieratchy, so if you take out the bottom blocks, the whole lot will come down. This will form a sort of puzzle element where you need to drop some blocks to break them - I haven't fleshed that bit out yet. Also, got the level start sequence in place and the way the bonus stars appear in the arc of your swing if you are swinging in a nice rythm.

Started roughing out some ideas for the early tutorial levels. I'm going with a sketchy blueprint style as that seemed to fit. Still all WIP - hopefully I should have a complete level in the next week.

Added the initial functionality for pickup bonuses and simple VFX. I had the idea that when the bonuses appear they will sketch themselves in. That's why there's all the sketch stars in the screenshot. It's a hand drawn animation which is a style I might adopt for other things. When they finish appearing they will take on a more solid form, but I haven't got round to that yet.

I've been having some issues with the garbage collector triggering more often than I'd like. I tracked one problem down to me creating a new matrix array everytime I drew a sprite - which was alot of matrices. I fixed that one, but there seem to be some less frequent ones still cropping up now. I'll track it down.

Added some placeholder music. I wanted to test if it had any impact on framerate. Seems ok at the moment. I fell into the trap of the garbage collector collecting the MediaPlayer and killing the music. Fixed by making the scope more global.

Also have a company name and logo:

Got the scores and title screen roughed in. Things will probably slow down a bit now but hopefully I've built up a bit of momentum...

Based on playing with the fixed grapple points, I've made it harder to miss and fall. Also, the game always picks the nearest grapple point to where the robot is - it had been using the touch position. This makes it much simpler to just swipe and tap anywhere on the screen which should work better with different display sizes.

Grapple points are in! They are currently static positions - I have big plans for moving grapple points, breakable ones etc, but I thought I better take it one step at a time.

What adding these has revealed is that the game could easily get too difficult. At the moment, if you try to grab a grapple point that is out of reach, you fall. This was fine when I was just grappling to any position you touch on the screen, but becomes annoyingly tough when you have fixed points.

I want the game to be accessible and fun, so I'll need to remix the ingredients to get the balance right.

The next thing I need to decide is what the goal is...

Level Manager

Finally got some time to work on this. I've added the level manager, so now I can have huge sprawling levels without killing the CPU with trying to render loads of off-screen sprites. I ended up implementing it as a set of configurable culling grids that sit at a given depth in the world. Because the game is largely 2D, I can split the scene into discrete slices and add a culling grid for that slice.
Each cell in the grid holds a list of sprites that cover that cell. I then just find which grid cells are visible using a sort of simplified frustum cull - as far as OpenGL is concerned the game is 3D.

I also created a simple level setup tool that I can use to quickly layout a level. This is on the PC and will not be part of the final game.

Next step is to add the actual elements you can grapple...