writeRadialGradient method

int writeRadialGradient(VectorGraphicsBuffer buffer, { required double centerX, required double centerY, required double radius, required double? focalX, required double? focalY, required Int32List colors, required Float32List? offsets, required Float64List? transform, required int tileMode, })

Write a radial gradient into the current buffer.

focalX and focalY must be either both null or both non-null.

Implementation

int writeRadialGradient(
  VectorGraphicsBuffer buffer, {
  required double centerX,
  required double centerY,
  required double radius,
  required double? focalX,
  required double? focalY,
  required Int32List colors,
  required Float32List? offsets,
  required Float64List? transform,
  required int tileMode,
}) {
  assert((focalX == null && focalY == null) ||
      (focalX != null && focalY != null));
  assert(transform == null || transform.length == 16);
  buffer._checkPhase(_CurrentSection.shaders);

  final int shaderId = buffer._nextShaderId++;
  assert(shaderId < kMaxId);
  buffer._putUint8(_radialGradientTag);
  buffer._putUint16(shaderId);
  buffer._putFloat32(centerX);
  buffer._putFloat32(centerY);
  buffer._putFloat32(radius);

  if (focalX != null) {
    buffer._putUint8(1);
    buffer._putFloat32(focalX);
    buffer._putFloat32(focalY!);
  } else {
    buffer._putUint8(0);
  }
  buffer._putUint16(colors.length);
  buffer._putInt32List(colors);
  if (offsets != null) {
    buffer._putUint16(offsets.length);
    buffer._putFloat32List(offsets);
  } else {
    buffer._putUint16(0);
  }
  buffer._writeTransform(transform);
  buffer._putUint8(tileMode);
  return shaderId;
}