Particles: AddBulletParticleToBuffer

       Name: AddBulletParticleToBuffer                               [Show more]
       Type: Subroutine
   Category: Particles
    Summary: Add a bullet particle to the particle data buffer
  Deep dive: Particles and particle clouds
             Collisions and bullets
    Context: See this subroutine in context in the source code
 References: This subroutine is called as follows:
             * MoveAndDrawPlayer (Part 5 of 5) calls AddBulletParticleToBuffer


 Arguments:

   (R0, R1, R2)                     Particle coordinate

   (R3, R4, R5)                     Particle velocity

   R6                               Particle lifespan counter (i.e. how many
                                    iterations around the main loop before the
                                    particle expires)

   R7                               Particle flags

   R8                               Magnitude of the random element that's added
                                    to the velocity, with a larger figure giving
                                    a smaller random element; the actual range
                                    is +/- 2^(32 - R8)

   R9                               Magnitude of the random element that's added
                                    to the particle lifespan, with a larger
                                    figure giving a smaller random element; the
                                    actual range is 0 to 2^(32 - R9)


.AddBulletParticleToBuffer

 STMFD   R13!, {R8, R14}            \ Store R8 and the return address on the
                                    \ stack, so the call to StoreParticleData
                                    \ can return properly

 B       StoreParticleData          \ Jump to StoreParticleData to store the
                                    \ particle in the particle data buffer,
                                    \ returning from the subroutine using a tail
                                    \ call