suck - Radial Displacement Function #

Radial pixel displacement with fluid dynamics

Syntax #

(suck strength)                ; Radial effect from screen center
(suck strength centerX centerY) ; Radial effect from custom point

Parameters #

• strength: Displacement intensity (positive = inward, negative = outward)
• centerX, centerY: Optional center point (defaults to screen center)

Behavior #

• Moves pixels radially toward or away from center point
• Uses polar coordinate transformation for smooth circular patterns
• Positive strength creates inward vortex effect
• Negative strength creates outward expansion effect

Examples #

Basic Effects #

(suck 1)           ; Strong inward vortex
(suck -0.5)        ; Gentle outward flow
(suck 0.1)         ; Subtle breathing effect

Animation Patterns #

(s1 (suck 0.5))    ; Gentle pulse every second
(s0.1 (suck 0.1))  ; Rapid micro-movements
["2s..." 1 0 -1]   ; Multi-phase timing with varying strength

Combined Transformations #

(blur 1)           ; Soften edges first
(suck 0.2)         ; Add subtle vortex
(contrast 1.2)     ; Enhance final result

Custom Center Points #

(suck 0.5 100 100)    ; Vortex at specific coordinate
(suck -0.3 width height) ; Outward from bottom-right

Implementation Notes #

• Uses polar coordinate mathematics for smooth radial displacement
• Bilinear interpolation provides anti-aliasing
• Accumulation system prevents excessive computation
• Compatible with embedded layer system and mask regions
• Optimized for real-time performance

Related Functions #

• scroll - Translation transformation
• zoom - Scale transformation
• spin - Rotation transformation
• blur - Blur effect (often combined with suck)