BrushGradientAddColor - ProGUI Reference Manual

Syntax

Success = BrushGradientAddColor(Brush, Position.f, Color.l, Opacity.f)

Description

Adds an intermediate color stop to an existing linear or radial gradient brush. This allows for creating gradients with more than two colors.

Parameters

Brush
The handle of the existing linear or radial gradient brush to modify.

Position.f
The relative position (0.0 to 1.0) along the gradient line (for linear) or radius (for radial) where this color stop should be placed.

Color.l
The color (RGB value) for this stop.

Opacity.f
The opacity (0.0 to 1.0) for this stop.

Return Value

Returns #True if the color stop was successfully added, or #False if the brush handle was invalid or not a gradient brush.

Remarks

This function modifies the existing gradient brush by adding a new color transition point. The underlying graphics resources for the brush are typically recreated. Positions should ideally be added in increasing order, although the underlying system might sort them. Adding stops allows for complex color blends.

Example

IncludeFile "ProGUI_PB.pbi"

StartProGUI()

Global MyGradient

Procedure DrawHandler(Window, EventType, *EventData.PG_EventDraw)
  DrawClear(RGB(240, 240, 240), 1)
  DrawBoxFill(50, 50, 300, 200, MyGradient)
EndProcedure

MyWindow = CreateWindow(0, 0, 400, 300, "Adding Gradient Stops")

If MyWindow
  ; Create a simple 2-color gradient first
  MyGradient = CreateBrushGradientLinear(50, 0, 350, 0, RGB(255, 0, 0), 1.0, RGB(0, 0, 255), 1.0) ; Red to Blue
   
  If MyGradient
      ; Add a yellow stop in the middle
      BrushGradientAddColor(MyGradient, 0.5, RGB(255, 255, 0), 1.0)
      ; Add a cyan stop
      BrushGradientAddColor(MyGradient, 0.8, RGB(0, 255, 255), 0.7) ; Semi-transparent cyan

      AddEventHandler(MyWindow, #PG_Event_Draw, @DrawHandler())
      WindowShow(MyWindow, #True, #PG_Window_ScreenCentered)

      Repeat
          Event = WaitWindowEvent()
      Until Event = #PB_Event_CloseWindow

      FreeBrush(MyGradient) ; Free the brush
  EndIf
EndIf

StopProGUI()

Supported OS

Windows, Linux