API Reference: Color & Encoding

This page covers high-precision color representation, pixel formats, alpha interpretation, and color spaces.

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Color4f

Color4f represents a color using four floating-point values (RGBA), each typically ranging from 0.0 to 1.0. This allows for much higher precision than traditional 8-bit integers.

Constructors

• new Color4f(r, g, b, a)
• new Color4f(r, g, b): Opaque color (alpha = 1.0).
• new Color4f(int color): Converts a standard ARGB 8888 integer to float components.

Methods

• toColor(): Converts back to an ARGB 8888 integer.
• makeLerp(other, weight): Linearly interpolates between two colors.

Example

Color4f red = new Color4f(1f, 0f, 0f, 1f);
Color4f halfTransparentBlue = new Color4f(0f, 0f, 1f, 0.5f);

// Usage in Paint
Paint paint = new Paint().setColor4f(red, ColorSpace.getSRGB());

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ColorType

ColorType describes how bits are arranged in a pixel (e.g., channel order and bit depth).

Common Types

• RGBA_8888: 8 bits per channel, red first.
• BGRA_8888: 8 bits per channel, blue first (common on Windows).
• N32: Native 32-bit format for the current platform (usually maps to RGBA or BGRA).
• F16: 16-bit half-float per channel (High Dynamic Range).
• GRAY_8: single 8-bit channel for grayscale.
• ALPHA_8: single 8-bit channel for transparency masks.

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ColorAlphaType

ColorAlphaType describes how the alpha channel should be interpreted.

• OPAQUE: All pixels are fully opaque; alpha channel is ignored.
• PREMUL: Color components are multiplied by alpha (Standard for Skia performance).
• UNPREMUL: Color components are independent of alpha.

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ColorSpace

ColorSpace defines the range (gamut) and linearity of colors.

Common Color Spaces

• ColorSpace.getSRGB(): The standard color space for web and most monitors.
• ColorSpace.getSRGBLinear(): sRGB with a linear transfer function (useful for math/blending).
• ColorSpace.getDisplayP3(): Wide gamut color space used by modern Apple devices.

Methods

• isSRGB(): Returns true if the space is sRGB.
• isGammaLinear(): Returns true if the transfer function is linear.
• convert(to, color): Converts a Color4f from this space to another.

Usage Example

// Creating an ImageInfo with specific encoding
ImageInfo info = new ImageInfo(
    800, 600, 
    ColorType.N32, 
    ColorAlphaType.PREMUL, 
    ColorSpace.getSRGB()
);