Effects and lighting

#Particles

The VFX and Effects blocks create particles at the centre of the object that runs them:

• Particle burst: a one-off burst with a preset (sparkles, fire, smoke, confetti) and a particle count.
• Custom particle burst: full control over colour, speed, lifetime, size, end size, gravity, angle, spread, drag and shape (circle, square, spark, ring).
• Start particle emitter and Stop particle emitter: a named emitter that keeps producing particles at a rate per second and follows the object.
• Shockwave ring: an expanding ring.
• Burst particles and Movement trail: simple helpers. Run the trail every frame (for example in On Update); it leaves particles as the object moves.
• Clear all effects removes every particle, emitter and flash.

#Flash, shake and fades

• Screen flash: fills the screen with a colour that fades out over the duration, for hits and explosions. UI stays on top of it.
• Shake Camera: moves the camera randomly for a duration. Intensity is the maximum offset in pixels, so values like 6 or 10 are clearly visible.
• Fade screen: fades a full-screen colour in (opacity 1) or out (opacity 0), over everything including UI.
• Blink: flashes one object on and off, for example while a character is invulnerable.

#Lighting

The Lighting blocks darken the world and let lights cut through the darkness.

1. Darken the world: Set ambient light with a colour and a darkness from 0 (daylight) to 1 (pitch black). With over seconds above 0 it fades smoothly, for example at dusk.
2. Give objects a light: run Add light to this object on a torch, a lantern or a glowing creature. Set its radius, color, intensity, flicker (0 to 1, for fire) and an offset from the object's centre. The light follows the object.
3. Change it later with Set light of this object (it can fade over seconds) or turn it off with Remove light of this object.

• Lights are only visible where there is darkness. With ambient darkness at 0 the scene is fully lit and lights have no effect.
• UI objects, and objects pinned to the screen with Pin to screen that are drawn above the world, are never darkened, so the HUD stays readable.
• Run Add light before Set light: Set light on an object without a light stops Play with an error.
• Lighting starts from daylight every time Play starts or a scene loads. A scene can have up to 256 lights.

#Post effects

Post effects change the look of the whole world and work with or without darkness:

• Set vignette (post effect): darkens the screen edges with a colour.
• Set color grade (post effect): tints the world by multiplying it with a colour, for a warm dusk, a cold night or sepia.
• Set retro scanlines (post effect): subtle CRT scanlines for a retro feel.
• Clear post effects removes all three.

Each effect has a strength from 0 to 1. Lighting and post effects are drawn on the CPU with Qt's QPainter composition modes; they are not GPU shaders. The light map is composed at a reduced resolution, which keeps it light enough for 2D games and looks the same in the editor and in exported games.

#See it in a real game

Bramblelight uses every lighting block: ambient darkness per area, torches and window glows with flicker, wisps, a lantern that follows the player, and vignette, colour grade and scanlines. Open it from Home and read the scripts of its torches and of the player. See Examples.