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Difference between revisions of "Improve ObjectMove subroutines"

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{{GuideBy|redhotsonic}}
 
{{GuideBy|redhotsonic}}
  
(S1 Hivebrain Version By: LuigiXHero)
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''(Hivebrain Addition by [[User:Luigi Hero|Luigi Hero]])''
  
 
Want to speed up your hack?
 
Want to speed up your hack?

Revision as of 20:11, 2 August 2015

(Original guide by redhotsonic)

(Hivebrain Addition by Luigi Hero)

Want to speed up your hack?

In S1, S2 and S3K, there are two subroutines: one allows an object to move about, and the other does the same, except it applies gravity to it. In S1, these subroutines are SpeedToPos, and ObjectFall, respectively. In S2, these are ObjectMove and ObjectMoveAndFall. Finally, in S3K, these are MoveSprite2 and MoveSprite.

S3K has the same subroutines except the code is a bit shorter and therefore, it's faster. It may not look much faster, but again, with all the objects on screen, it has to apply it for every frame.

So, let's change our subroutines to work more like S3K's. To do this, it's really simple.

Sonic 1 Hivebrain

First find ObjectFall and change this: <asm> ObjectFall: move.l 8(a0),d2 move.l $C(a0),d3 move.w $10(a0),d0 ext.l d0 asl.l #8,d0 add.l d0,d2 move.w $12(a0),d0 addi.w #$38,$12(a0) ; increase vertical speed ext.l d0 asl.l #8,d0 add.l d0,d3 move.l d2,8(a0) move.l d3,$C(a0) rts

End of function ObjectFall

</asm>

To this: <asm> ObjectFall: move.w $10(a0),d0 ext.l d0 lsl.l #8,d0 add.l d0,8(a0) move.w $12(a0),d0 addi.w #$38,$12(a0) ; increase vertical speed ext.l d0 lsl.l #8,d0 add.l d0,$C(a0) rts

End of function ObjectFall

</asm>

Next, find SpeedToPos and change this: <asm> SpeedToPos: move.l 8(a0),d2 move.l $C(a0),d3 move.w $10(a0),d0 ; load horizontal speed ext.l d0 asl.l #8,d0 ; multiply speed by $100 add.l d0,d2 ; add to x-axis position move.w $12(a0),d0 ; load vertical speed ext.l d0 asl.l #8,d0 ; multiply by $100 add.l d0,d3 ; add to y-axis position move.l d2,8(a0) ; update x-axis position move.l d3,$C(a0) ; update y-axis position rts

End of function SpeedToPos

</asm>

to this: <asm> SpeedToPos: move.w $10(a0),d0 ; load horizontal speed ext.l d0 lsl.l #8,d0 ; multiply speed by $100 add.l d0,8(a0) ; add to x-axis position move.w $12(a0),d0 ; load vertical speed ext.l d0 lsl.l #8,d0 ; multiply by $100 add.l d0,$C(a0) ; add to y-axis position rts

End of function SpeedToPos

</asm>

Sonic 1 Git/SVN

Open "_incObj/sub ObjectFall.asm" and change this: <asm> ObjectFall: move.l obX(a0),d2 move.l obY(a0),d3 move.w obVelX(a0),d0 ext.l d0 asl.l #8,d0 add.l d0,d2 move.w obVelY(a0),d0 addi.w #$38,obVelY(a0) ; increase vertical speed ext.l d0 asl.l #8,d0 add.l d0,d3 move.l d2,obX(a0) move.l d3,obY(a0) rts

End of function ObjectFall

</asm>

To this: <asm> ObjectFall: move.w obVelX(a0),d0 ext.l d0 lsl.l #8,d0 add.l d0,obX(a0) move.w obVelY(a0),d0 addi.w #$38,obVelY(a0) ; increase vertical speed ext.l d0 lsl.l #8,d0 add.l d0,obY(a0) rts

End of function ObjectFall

</asm>

Next, open "_incObj/sub SpeedToPos.asm" and change this: <asm> SpeedToPos: move.l obX(a0),d2 move.l obY(a0),d3 move.w obVelX(a0),d0 ; load horizontal speed ext.l d0 asl.l #8,d0 ; multiply speed by $100 add.l d0,d2 ; add to x-axis position move.w obVelY(a0),d0 ; load vertical speed ext.l d0 asl.l #8,d0 ; multiply by $100 add.l d0,d3 ; add to y-axis position move.l d2,obX(a0) ; update x-axis position move.l d3,obY(a0) ; update y-axis position rts

End of function SpeedToPos

</asm>

to this: <asm> SpeedToPos: move.w obVelX(a0),d0 ; load horizontal speed ext.l d0 lsl.l #8,d0 ; multiply speed by $100 add.l d0,obX(a0) ; add to x-axis position move.w obVelY(a0),d0 ; load vertical speed ext.l d0 lsl.l #8,d0 ; multiply by $100 add.l d0,obY(a0) ; add to y-axis position rts

End of function SpeedToPos

</asm>

Sonic 2

Go to "ObjectMoveAndFall:" and change this: <asm> ObjectMoveAndFall: move.l x_pos(a0),d2 ; load x position move.l y_pos(a0),d3 ; load y position move.w x_vel(a0),d0 ; load x speed ext.l d0 asl.l #8,d0 ; shift velocity to line up with the middle 16 bits of the 32-bit position add.l d0,d2 ; add x speed to x position ; note this affects the subpixel position x_sub(a0) = 2+x_pos(a0) move.w y_vel(a0),d0 ; load y speed addi.w #$38,y_vel(a0) ; increase vertical speed (apply gravity) ext.l d0 asl.l #8,d0 ; shift velocity to line up with the middle 16 bits of the 32-bit position add.l d0,d3 ; add old y speed to y position ; note this affects the subpixel position y_sub(a0) = 2+y_pos(a0) move.l d2,x_pos(a0) ; store new x position move.l d3,y_pos(a0) ; store new y position rts

End of function ObjectMoveAndFall

</asm>

To this: <asm> ObjectMoveAndFall: move.w x_vel(a0),d0 ; load x speed ext.l d0 lsl.l #8,d0 ; shift velocity to line up with the middle 16 bits of the 32-bit position add.l d0,x_pos(a0) ; add x speed to x position ; note this affects the subpixel position x_sub(a0) = 2+x_pos(a0) move.w y_vel(a0),d0 ; load y speed addi.w #$38,y_vel(a0) ; increase vertical speed (apply gravity) ext.l d0 lsl.l #8,d0 ; shift velocity to line up with the middle 16 bits of the 32-bit position add.l d0,y_pos(a0) ; add old y speed to y position ; note this affects the subpixel position y_sub(a0) = 2+y_pos(a0) rts

End of function ObjectMoveAndFall

</asm>

Next, go to "ObjectMove:" and change this: <asm> ObjectMove: move.l x_pos(a0),d2 ; load x position move.l y_pos(a0),d3 ; load y position move.w x_vel(a0),d0 ; load horizontal speed ext.l d0 asl.l #8,d0 ; shift velocity to line up with the middle 16 bits of the 32-bit position add.l d0,d2 ; add to x-axis position ; note this affects the subpixel position x_sub(a0) = 2+x_pos(a0) move.w y_vel(a0),d0 ; load vertical speed ext.l d0 asl.l #8,d0 ; shift velocity to line up with the middle 16 bits of the 32-bit position add.l d0,d3 ; add to y-axis position ; note this affects the subpixel position y_sub(a0) = 2+y_pos(a0) move.l d2,x_pos(a0) ; update x-axis position move.l d3,y_pos(a0) ; update y-axis position rts

End of function ObjectMove

</asm>

to this: <asm> ObjectMove: move.w x_vel(a0),d0 ; load horizontal speed ext.l d0 lsl.l #8,d0 ; shift velocity to line up with the middle 16 bits of the 32-bit position add.l d0,x_pos(a0) ; add to x-axis position ; note this affects the subpixel position x_sub(a0) = 2+x_pos(a0) move.w y_vel(a0),d0 ; load vertical speed ext.l d0 lsl.l #8,d0 ; shift velocity to line up with the middle 16 bits of the 32-bit position add.l d0,y_pos(a0) ; add to y-axis position ; note this affects the subpixel position y_sub(a0) = 2+y_pos(a0) rts

End of function ObjectMove

</asm>

Conclusion

That's that. For any object that has to move, it will now do this coding a lot quicker each frame.

SCHG How-To Guide: Sonic the Hedgehog (16-bit)
Fixing Bugs
Fix Demo Playback | Fix a Race Condition with Pattern Load Cues | Fix the SEGA Sound | Display the Press Start Button Text | Fix the Level Select Menu | Fix the Hidden Points Bug | Fix Accidental Deletion of Scattered Rings | Fix Ring Timers | Fix the Walk-Jump Bug | Correct Drowning Bugs | Fix the Death Boundary Bug | Fix the Camera Follow Bug | Fix Song Restoration Bugs | Fix the HUD Blinking | Fix the Level Select Graphics Bug | Fix a remember sprite related bug
Changing Design Choices
Change Spike Behavior | Collide with Water After Being Hurt | Fix Special Stage Jumping Physics | Improve the Fade In\Fade Out Progression Routines | Fix Scattered Rings' Underwater Physics | Remove the Speed Cap | Port the REV01 Background Effects | Port Sonic 2's Level Art Loader | Retain Rings Between Acts | Add Sonic 2 (Simon Wai Prototype) Level Select | Improve ObjectMove Subroutines | Port Sonic 2 Level Select
Adding Features
Add Spin Dash ( Part 1 / Part 2 / Part 3 / Part 4 ) | Add Eggman Monitor | Add Super Sonic | Add the Air Roll
Sound Features
Expand the Sound Index | Play Different Songs Per Act | Port Sonic 2 Final Sound Driver | Port Sonic 3's Sound Driver | Port Flamewing's Sonic 3 & Knuckles Sound Driver | Change The SEGA Sound
Extending the Game
Load Chunks From ROM | Add Extra Characters | Make an Alternative Title Screen | Use Dynamic Tilesets | Make GHZ Load Alternate Art | Make Ending Load Alternate Art | Add a New Zone | Set Up the Goggle Monitor | Add New Moves | Add a Dynamic Collision System | Dynamic Special Stage Walls System | Extend Sprite Mappings and Art Limit | Enigma Credits | Use Dynamic Palettes
Miscellaneous
Convert the Hivebrain 2005 Disassembly to ASM68K
Split Disassembly Guides
Set Up a Split Disassembly | Basic Level Editing | Basic Art Editing | Basic ASM Editing (Spin Dash)
SCHG How-To Guide: Sonic the Hedgehog 2 (16-bit)
Fixing Bugs
Fix Demo Playback | Fix a Race Condition with Pattern Load Cues | Fix Super Sonic Bugs | Use Correct Height When Roll Jumping | Fix Jump Height Bug When Exiting Water | Fix Screen Boundary Spin Dash Bug | Correct Drowning Bugs | Fix Camera Y Position for Tails | Fix Tails Subanimation Error | Fix Tails' Respawn Speeds | Fix Accidental Deletion of Scattered Rings | Fix Ring Timers | Fix Rexon Crash | Fix Monitor Collision Bug | Fix EHZ Deformation Bug | Correct CPZ Boss Attack Behavior | Fix Bug in ARZ Boss Arrow's Platform Behavior | Fix ARZ Boss Walking on Air Glitch | Fix ARZ Boss Sprite Behavior | Fix Multiple CNZ Boss Bugs | Fix HTZ Background Scrolling Mountains | Fix OOZ Launcher Speed Up Glitch | Fix DEZ Giant Mech Collision Glitch | Fix Boss Deconstruction Behavior | Fix Speed Bugs | Fix 14 Continues Cheat | Fix Debug Mode Crash | Fix 99+ Lives | Fix Sonic 2's Sega Screen
Design Choices
Remove the Air Speed Cap | Disable Floor Collision While Dying | Modify Super Sonic Transformation Methods & Behavior | Enable/Disable Tails in Certain Levels | Collide with Water After Being Hurt | Retain Rings When Returning at a Star Post | Improve the Fade In\Fade Out Progression Routines | Fix Scattered Rings' Underwater Physics | Insert LZ Water Ripple Effect | Restore Lost CPZ Boss Feature | Prevent SCZ Tornado Spin Dash Death | Improve ObjectMove Subroutines | Port S3K Rings Manager | Port S3K Object Manager | Port S3K Priority Manager | Edit Level Order with ASM‎ | Alter Ring Requirements in Special Stages | Make Special Stage Characters Use Normal DPLCs | Speed Up Ring Loss Process | Change spike behaviour in Sonic 2
Adding Features
Create Insta-kill and High Jump Monitors | Create Clone and Special Stage Monitors | Port Knuckles
Sound Features
Expand Music Index to Start at $00 | Port Sonic 1 Sound Driver | Port Sonic 2 Clone Driver | Port Sonic 3 Sound Driver | Port Flamewing's Sonic 3 & Knuckles Sound Driver | Expand the Music Index to Start at $00 (Sonic 2 Clone Driver Version) | Play Different Songs Per Act
Extending the Game
Extend the Level Index Past $10 | Extend the Level Select | Extend Water Tables | Add Extra Characters | Free Up 2 Universal SSTs