ReflectionEffectLib — Plan9Basic Documentation

Overview

ReflectionEffectLib creates mirror-like reflections below visual controls, wrapping the FireMonkey TReflectionEffect component. The effect renders a fading, inverted copy of the control beneath it — similar to iOS-style glossy reflections or objects reflected on a polished surface.

Property	Details
Library	`ReflectionEffectLib`
Prefix	`reflection_`
Wraps	`TReflectionEffect`
Functions	16
Type	Visual effect (decorative)

Category	Count	Description
Creation / Destruction	2	Create and free effect
Length	2	Get/set reflection height
Opacity	2	Get/set reflection transparency
Offset	2	Get/set gap from control
Effect Control	4	Enabled and trigger get/set
Error Handling	4	Error codes and messages

🪄 Glossy Surfaces: This effect adds a polished, professional look to UI elements. Use subtle opacity (0.2–0.4) and moderate length (0.3–0.5) for the most realistic appearance.

Cross-Platform Support

Platform	Support
Windows	✅ Full support
Linux	✅ Full support
Android	✅ Full support

Creation & Destruction

reflection#(parent#)

Creates a new reflection effect attached to the specified visual control.

Parameter	Type	Description
`parent#`	Pointer	Target visual control
Returns	Pointer	Effect handle, or 0 on failure

reflection_free(effect#)

Destroys the effect and releases associated resources.

Error Handling

Function	Signature	Description
`reflection_error()`	`reflection_error@`	Returns last error code (0 = none)
`reflection_errormsg$()`	`reflection_errormsg$@`	Returns last error message
`reflection_strerror$(code)`	`reflection_strerror$@n`	Converts error code to text
`reflection_clearerror()`	`reflection_clearerror@`	Clears the error state

Length

Controls how much of the control is reflected. A value of 1.0 reflects the entire control; 0.5 reflects only the bottom half.

Function	Signature	Description
`reflection_length#(effect#, value)`	`reflection_length#@#n`	Set reflection height (0–1)
`reflection_length(effect#)`	`reflection_length@#`	Get reflection height

Value	Effect
`0.2–0.3`	Short, subtle reflection
`0.4–0.5`	Medium reflection (default range)
`0.6–0.8`	Tall reflection
`1.0`	Full mirror image

Opacity

Controls the transparency of the reflection. Lower values create a more subtle, realistic effect.

Function	Signature	Description
`reflection_opacity#(effect#, value)`	`reflection_opacity#@#n`	Set opacity (0–1)
`reflection_opacity(effect#)`	`reflection_opacity@#`	Get opacity

Offset

Sets the gap in pixels between the control and its reflection, creating visual separation.

Function	Signature	Description
`reflection_offset#(effect#, pixels)`	`reflection_offset#@#n`	Set gap (pixels)
`reflection_offset(effect#)`	`reflection_offset@#`	Get gap

Effect Control

Function	Signature	Description
`reflection_enabled#(effect#, value)`	`reflection_enabled#@#n`	Enable (1) or disable (0)
`reflection_enabled(effect#)`	`reflection_enabled@#`	Gets enabled state
`reflection_trigger#(effect#, trigger$)`	`reflection_trigger#@#$`	Sets trigger string
`reflection_trigger$(effect#)`	`reflection_trigger$@#`	Gets trigger string

Complete Examples

Example 1: Basic Reflection

╯ basic-reflection.bas─◻✕
let frm# = Pointer#(0)
let rect# = Pointer#(0)
let refl# = Pointer#(0)

frm# = form#("Reflection Demo", 400, 350)

rect# = rectangle#(frm#)
rectangle_bounds#(rect#, 100, 50, 200, 100)
rectangle_fill#(rect#, "SteelBlue")

refl# = reflection#(rect#)
reflection_length#(refl#, 0.5)
reflection_opacity#(refl#, 0.4)
reflection_offset#(refl#, 2)

form_show(frm#)

Example 2: Reflection Controls

╯ reflection-controls.bas─◻✕
let frm# = Pointer#(0)
let rect# = Pointer#(0)
let refl# = Pointer#(0)
let lbl# = Pointer#(0)

frm# = form#("Reflection Controls", 450, 380)

rect# = rectangle#(frm#)
rectangle_bounds#(rect#, 125, 40, 200, 100)
rectangle_fill#(rect#, "Navy")

refl# = reflection#(rect#)
reflection_length#(refl#, 0.5)
reflection_opacity#(refl#, 0.5)

lbl# = label#(frm#, "Length: 50%  Opacity: 50%", 120, 220)

let btn1# = button#(frm#, "Len 25%")
button_bounds#(btn1#, 40, 260, 80, 30)
button_onclick#(btn1#, "SetLen25")

let btn2# = button#(frm#, "Len 50%")
button_bounds#(btn2#, 130, 260, 80, 30)
button_onclick#(btn2#, "SetLen50")

let btn3# = button#(frm#, "Len 75%")
button_bounds#(btn3#, 220, 260, 80, 30)
button_onclick#(btn3#, "SetLen75")

let btn4# = button#(frm#, "Toggle")
button_bounds#(btn4#, 310, 260, 80, 30)
button_onclick#(btn4#, "Toggle")

form_show(frm#)

function SetLen25(sender#)
  reflection_length#(refl#, 0.25)
  label_text#(lbl#, "Length: 25%")
endfunction

function SetLen50(sender#)
  reflection_length#(refl#, 0.50)
  label_text#(lbl#, "Length: 50%")
endfunction

function SetLen75(sender#)
  reflection_length#(refl#, 0.75)
  label_text#(lbl#, "Length: 75%")
endfunction

function Toggle(sender#)
  if reflection_enabled(refl#) = 1 then
    reflection_enabled#(refl#, 0)
    label_text#(lbl#, "Reflection: OFF")
  else
    reflection_enabled#(refl#, 1)
    label_text#(lbl#, "Reflection: ON")
  endif
endfunction

Example 3: Gallery with Reflections

╯ reflection-gallery.bas─◻✕
let frm# = Pointer#(0)

frm# = form#("Reflection Gallery", 500, 350)

' Create 3 items with reflections
let rect1# = rectangle#(frm#)
rectangle_bounds#(rect1#, 50, 50, 120, 80)
rectangle_fill#(rect1#, "Red")
let refl1# = reflection#(rect1#)
reflection_length#(refl1#, 0.4)
reflection_opacity#(refl1#, 0.3)

let rect2# = rectangle#(frm#)
rectangle_bounds#(rect2#, 190, 50, 120, 80)
rectangle_fill#(rect2#, "Green")
let refl2# = reflection#(rect2#)
reflection_length#(refl2#, 0.4)
reflection_opacity#(refl2#, 0.3)

let rect3# = rectangle#(frm#)
rectangle_bounds#(rect3#, 330, 50, 120, 80)
rectangle_fill#(rect3#, "Blue")
let refl3# = reflection#(rect3#)
reflection_length#(refl3#, 0.4)
reflection_opacity#(refl3#, 0.3)

form_show(frm#)

Best Practices

Practice	Why
Use opacity 0.2–0.4 for professional look	Too opaque looks unrealistic
Keep length at 0.3–0.5	Realistic reflections fade before full length
Add small offset (2–4 px)	Creates visual separation from control
Works best on solid colored shapes	Complex controls may have uneven reflections
Leave space below the control	The reflection renders beneath the control's bounds

Quick Reference

Function	Signature	Description
CREATION & DESTRUCTION
`reflection#(parent#)`	`reflection#@#`	Create effect
`reflection_free(effect#)`	`reflection_free@#`	Destroy effect
LENGTH
`reflection_length#(effect#, value)`	`reflection_length#@#n`	Set height (0–1)
`reflection_length(effect#)`	`reflection_length@#`	Get height
OPACITY
`reflection_opacity#(effect#, value)`	`reflection_opacity#@#n`	Set opacity (0–1)
`reflection_opacity(effect#)`	`reflection_opacity@#`	Get opacity
OFFSET
`reflection_offset#(effect#, pixels)`	`reflection_offset#@#n`	Set gap (pixels)
`reflection_offset(effect#)`	`reflection_offset@#`	Get gap
EFFECT CONTROL
`reflection_enabled#(effect#, value)`	`reflection_enabled#@#n`	Enable/disable
`reflection_enabled(effect#)`	`reflection_enabled@#`	Get enabled state
`reflection_trigger#(effect#, trigger$)`	`reflection_trigger#@#$`	Set trigger
`reflection_trigger$(effect#)`	`reflection_trigger$@#`	Get trigger
ERROR HANDLING
`reflection_error()`	`reflection_error@`	Last error code
`reflection_errormsg$()`	`reflection_errormsg$@`	Last error message
`reflection_strerror$(code)`	`reflection_strerror$@n`	Code to text
`reflection_clearerror()`	`reflection_clearerror@`	Clear error state

Library	Description
`ShadowEffectLib`	Drop shadow effects
`GlowEffectLib`	Outer glow effects
`InnerGlowEffectLib`	Inner glow effects