08-09-2018, 06:26 AM
For the first effect, the pulsating small shield, I would use a sprite with a perfect circle at fixed resolution and a single color, and then use a raster effect to change the palette value of that color.
The scaling circle to full screen is another issue, used also in Super Mario World as a transition after ending a level. I don't have a clue, it may be good idea to load it into an emulator with debugging support and inspect what's going on. I think that a "circle paint" routine in realtime would be too expensive for the SNES (but would be easily done in Tilengine on current hardware), and the use of a Mode-7 scaling background is not possible because the effect is overlaid on top of another layer(s).
Any other guess?
The scaling circle to full screen is another issue, used also in Super Mario World as a transition after ending a level. I don't have a clue, it may be good idea to load it into an emulator with debugging support and inspect what's going on. I think that a "circle paint" routine in realtime would be too expensive for the SNES (but would be easily done in Tilengine on current hardware), and the use of a Mode-7 scaling background is not possible because the effect is overlaid on top of another layer(s).
Any other guess?