export declare enum Location {
    BARYCENTRIC = 0,
    FRAG_COORD = 1,
    ABCD = 2,
    TXTY = 3,
    POSITION_SIZE = 4,
    ZINDEX_STROKE_WIDTH = 5,
    DROP_SHADOW_COLOR = 6,
    DROP_SHADOW = 7
}
export declare const vert = "\nlayout(std140) uniform SceneUniforms {\n  mat3 u_ProjectionMatrix;\n  mat3 u_ViewMatrix;\n  mat3 u_ViewProjectionInvMatrix;\n  vec4 u_BackgroundColor;\n  vec4 u_GridColor;\n  float u_ZoomScale;\n  float u_CheckboardStyle;\n};\n\n\n#ifdef USE_WIREFRAME\n  layout(location = 0) in vec3 a_Barycentric;\n  out vec3 v_Barycentric;\n#endif\n\nlayout(location = 1) in vec2 a_FragCoord;\n\n#ifdef USE_INSTANCES\n  layout(location = 2) in vec4 a_Abcd;\n  layout(location = 3) in vec2 a_Txty;\n  layout(location = 4) in vec4 a_PositionSize;\n  layout(location = 5) in vec4 a_ZIndexStrokeWidth;\n  layout(location = 6) in vec4 a_DropShadowColor;\n  layout(location = 7) in vec4 a_DropShadow;\n#else\n  layout(std140) uniform ShapeUniforms {\n    mat3 u_ModelMatrix;\n    vec4 u_PositionSize;\n    vec4 u_ZIndexStrokeWidth;\n    vec4 u_DropShadowColor;\n    vec4 u_DropShadow;\n  };\n#endif\n\nout vec2 v_Origin;\n#ifdef USE_INSTANCES\n  out float v_CornerRadius;\n  out vec4 v_DropShadowColor;\n  out vec4 v_DropShadow;\n#else\n#endif\nout vec2 v_Size;\nout vec2 v_Point;\n\nvoid main() {\n  \n#ifdef USE_WIREFRAME\n  v_Barycentric = a_Barycentric;\n#endif\n\n\n  mat3 model;\n  vec2 origin;\n  vec2 size;\n  float zIndex;\n  vec4 dropShadow;\n  float sizeAttenuation;\n\n  #ifdef USE_INSTANCES\n    model = mat3(a_Abcd.x, a_Abcd.y, 0, a_Abcd.z, a_Abcd.w, 0, a_Txty.x, a_Txty.y, 1);\n    origin = a_PositionSize.xy;\n    size = a_PositionSize.zw;\n    zIndex = a_ZIndexStrokeWidth.x;\n    dropShadow = a_DropShadow;\n    sizeAttenuation = a_ZIndexStrokeWidth.w;\n    v_CornerRadius = a_ZIndexStrokeWidth.z;\n    v_DropShadowColor = a_DropShadowColor;\n    v_DropShadow = dropShadow;\n  #else\n    model = u_ModelMatrix;\n    origin = u_PositionSize.xy;\n    size = u_PositionSize.zw;\n    zIndex = u_ZIndexStrokeWidth.x;\n    dropShadow = u_DropShadow;\n    sizeAttenuation = u_ZIndexStrokeWidth.w;\n  #endif\n\n  float scale = 1.0;\n  if (sizeAttenuation > 0.5) {\n    scale = 1.0 / u_ZoomScale;\n  }\n\n  // Set the bounds of the shadow and adjust its size based on the shadow's\n  // spread radius to achieve the spreading effect\n  float margin = 3.0 * dropShadow.z;\n\n  vec2 center = origin + size / 2.0;\n  vec2 sizeSign = sign(size);\n  size = abs(size);\n\n  // Recalculate the origin since the size could be negative\n  origin = center - size / 2.0 + dropShadow.xy * sizeSign;\n  v_Size = size;\n  v_Origin = origin;\n\n  origin -= margin;\n  size += 2.0 * margin;\n  \n  v_Point = center + a_FragCoord * (size / 2.0);\n\n  gl_Position = vec4((u_ProjectionMatrix \n    * u_ViewMatrix\n    * model \n    * vec3(center + a_FragCoord * (size / 2.0) * scale, 1)).xy, zIndex, 1);\n}\n";
export declare const frag = "\nlayout(std140) uniform SceneUniforms {\n  mat3 u_ProjectionMatrix;\n  mat3 u_ViewMatrix;\n  mat3 u_ViewProjectionInvMatrix;\n  vec4 u_BackgroundColor;\n  vec4 u_GridColor;\n  float u_ZoomScale;\n  float u_CheckboardStyle;\n};\n\n#ifdef USE_INSTANCES\n#else\n  layout(std140) uniform ShapeUniforms {\n    mat3 u_ModelMatrix;\n    vec4 u_PositionSize;\n    vec4 u_ZIndexStrokeWidth;\n    vec4 u_DropShadowColor;\n    vec4 u_DropShadow;\n  };\n#endif\n\nout vec4 outputColor;\n\n\n#ifdef USE_WIREFRAME\n  in vec3 v_Barycentric;\n\n  float edgeFactor() {\n    float u_WireframeLineWidth = 1.0;\n    vec3 d = fwidth(v_Barycentric);\n    vec3 a3 = smoothstep(vec3(0.0), d * u_WireframeLineWidth, v_Barycentric);\n    return min(min(a3.x, a3.y), a3.z);\n  }\n#endif\n\nin vec2 v_Origin;\n#ifdef USE_INSTANCES\n  in float v_CornerRadius;\n  in vec4 v_DropShadowColor;\n  in vec4 v_DropShadow;\n#else\n#endif\nin vec2 v_Size;\nin vec2 v_Point;\n\nfloat epsilon = 0.000001;\nfloat PI = 3.1415926;\n\n// A standard gaussian function, used for weighting samples\nfloat gaussian(float x, float sigma) {\n  return exp(-(x * x) / (2. * sigma * sigma)) / (sqrt(2. * PI) * sigma);\n}\n\n// This approximates the error function, needed for the gaussian integral\nvec2 erf(vec2 x) {\n  vec2 s = sign(x), a = abs(x);\n  x = 1.0 + (0.278393 + (0.230389 + 0.078108 * (a * a)) * a) * a;\n  x *= x;\n  return s - s / (x * x);\n}\n\n// @see https://raphlinus.github.io/graphics/2020/04/21/blurred-rounded-rects.html\n// vec2 erf7(vec2 x) {\n//   x = x * sqrt(2. * PI);\n//   vec2 xx = x * x;\n//   x = x + (0.24295 + (0.03395 + 0.0104 * xx) * xx) * (x * xx);\n//   return x / sqrt(1.0 + x * x);\n// }\n\nfloat rect_shadow(vec2 pixel_position, vec2 origin, vec2 size, float sigma) {\n  vec2 bottom_right = origin + size;\n  vec2 x_distance = vec2(pixel_position.x - origin.x, pixel_position.x - bottom_right.x);\n  vec2 y_distance = vec2(pixel_position.y - origin.y, pixel_position.y - bottom_right.y);\n  vec2 integral_x = 0.5 + 0.5 * erf(x_distance * (sqrt(0.5) / sigma));\n  vec2 integral_y = 0.5 + 0.5 * erf(y_distance * (sqrt(0.5) / sigma));\n  return (integral_x.x - integral_x.y) * (integral_y.x - integral_y.y);\n}\n\nfloat blur_along_x(float x, float y, float sigma, float corner, vec2 half_size) {\n  float delta = min(half_size.y - corner - abs(y), 0.0);\n  float curved = half_size.x - corner + sqrt(max(0., corner * corner - delta * delta));\n  vec2 integral = 0.5 + 0.5 * erf((x + vec2(-curved, curved)) * (sqrt(0.5) / sigma));\n  return integral.y - integral.x;\n}\n\nvoid main() {\n  float cornerRadius;\n  vec4 dropShadow;\n  vec4 dropShadowColor;\n  \n  #ifdef USE_INSTANCES\n    cornerRadius = v_CornerRadius;\n    dropShadowColor = v_DropShadowColor;\n    dropShadow = v_DropShadow;\n  #else\n    cornerRadius = u_ZIndexStrokeWidth.z;\n    dropShadowColor = u_DropShadowColor;\n    dropShadow = u_DropShadow;\n  #endif\n\n  float blur_radius = dropShadow.z;\n  if (blur_radius > 0.0) {\n    float alpha = 0.;\n    vec2 point = v_Point;\n    \n    if (cornerRadius > 0.0) {\n      vec2 half_size = v_Size / 2.0;\n      vec2 center = v_Origin + half_size;\n      vec2 center_to_point = point - center;\n\n      // The signal is only non-zero in a limited range, so don't waste samples\n      float low = center_to_point.y - half_size.y;\n      float high = center_to_point.y + half_size.y;\n      float start = clamp(-3. * blur_radius, low, high);\n      float end = clamp(3. * blur_radius, low, high);\n\n      // Accumulate samples (we can get away with surprisingly few samples)\n      float step = (end - start) / 4.;\n      float y = start + step * 0.5;\n      \n      for (int i = 0; i < 4; i++) {\n        alpha += blur_along_x(center_to_point.x, center_to_point.y - y, blur_radius,\n                              cornerRadius, half_size) *\n                gaussian(y, blur_radius) * step;\n        y += step;\n      }\n    } else {\n      alpha = rect_shadow(point, v_Origin, v_Size, blur_radius);\n    }\n\n    outputColor = dropShadowColor;\n    outputColor.a = alpha;\n\n    \n#ifdef USE_WIREFRAME\n  vec3 u_WireframeLineColor = vec3(0.0, 0.0, 0.0);\n\n  outputColor.xyz = mix(outputColor.xyz, u_WireframeLineColor, (1.0 - edgeFactor()));\n  if (any(lessThan(v_Barycentric, vec3(0.01)))) {\n    outputColor.a = 0.95;\n  }\n#endif\n\n  } else {\n    discard;\n  }\n}\n";