The AddSmallExplosionToBuffer subroutine - Lander on the Acorn Archimedes

       Name: AddSmallExplosionToBuffer                               [Show more]
       Type: Subroutine
   Category: Particles
    Summary: Add a small explosion to the particle data buffer
  Deep dive: Particles and particle clouds
    Context: See this subroutine in context in the source code
 References: This subroutine is called as follows:
             * BounceParticle calls AddSmallExplosionToBuffer
             * ProcessObjectDestruction calls AddSmallExplosionToBuffer


 Arguments:

   (R0, R1, R2)                     Explosion coordinates

   R7                               Particle flags


.AddSmallExplosionToBuffer

 MOV     R8, #3                     \ Set R8 = 3 and call AddExplosionToBuffer
 BL      AddExplosionToBuffer       \ to draw a small explosion at the given
                                    \ coordinates

 B       DeleteParticleData         \ Jump to DeleteParticleData to delete the
                                    \ particle, as it gets destroyed in the
                                    \ explosion, and return from the subroutine
                                    \ using a tail call

[X]

Subroutine AddExplosionToBuffer (category: Particles)

Create a big explosion of particles and add it to the particle data buffer

[X]

Subroutine DeleteParticleData (category: Particles)

Delete a particle from the particle data buffer and move the last particle's data down to take its place