sdk/fidl/fuchsia.hardware.display/layer.fidl

// Copyright 2023 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
library fuchsia.hardware.display;

/// Type of the internal value in [`fuchsia.hardware.display/LayerId`].
alias LayerIdValue = uint64;

/// Identifies a layer resource owned by a Display Coordinator client.
///
/// [`fuchsia.hardware.display/INVALID_DISP_ID`] represents an invalid value.
///
/// Values are managed by [`fuchsia.hardware.display/Coordinator`] clients, to
/// facilitate feed-forward dataflow.
///
/// Valid values uniquely identify "live" layers within a Display Coordinator
/// connection. The identifier of a layer destroyed via
/// [`fuchsia.hardware.display/Coordinator.DestroyLayer`] can be reused in a
/// subsequent [`fuchsia.hardware.display/Coordinator.CreateLayer`] call.
type LayerId = struct {
    value LayerIdValue;
};

// Rotations are applied counter-clockwise, and are applied before reflections.  Note: this doesn't
// affect the output region on the physical display; use the layer's `dest_frame` for that.  In
// other words, if you have a 600x300 image that you want to rotate 90 degrees without changing the
// aspect ratio, you need to use `ROT_90`, and also use a `dest_frame` of 300x600.
//
// The reflection enums refer to the axis across which reflection occurs.  For example, `REFLECT_X`
// means a reflection across the X-axis.  In other words: bottom becomes top.
type Transform = strict enum : uint8 {
    IDENTITY = 0;
    REFLECT_X = 1;
    REFLECT_Y = 2;
    ROT_90 = 3;
    ROT_180 = 4;
    ROT_270 = 5;
    ROT_90_REFLECT_X = 6;
    ROT_90_REFLECT_Y = 7;
};

type AlphaMode = strict enum : uint8 {
    // Alpha is disabled for the plane (default).
    DISABLE = 0;
    // Plane alpha is premultiplied.
    PREMULTIPLIED = 1;
    // Hardware should multiply the alpha and color channels when blending.
    HW_MULTIPLY = 2;
};

type Frame = struct {
    // (x_pos, y_pos) specifies the position of the upper-left corner
    // of the frame.
    x_pos uint32;
    y_pos uint32;
    width uint32;
    height uint32;
};

type ClientCompositionOpcode = strict enum : uint8 {
    // The client should convert the corresponding layer to a primary layer.
    CLIENT_USE_PRIMARY = 0;
    // The client should compose all layers with CLIENT_MERGE_BASE and CLIENT_MERGE_SRC
    // into a new, single primary layer at the CLIENT_MERGE_BASE layer's z-order. The
    // driver must accept a fullscreen layer with the default pixel format, but may
    // accept other layer parameters.
    //
    // CLIENT_MERGE_BASE will only be set on one layer per display.
    CLIENT_MERGE_BASE = 1;
    // See CLIENT_MERGE_BASE.
    CLIENT_MERGE_SRC = 2;
    // The client should provide a new image produced by scaling the source image
    // such that the dimensions of the new image's src_frame and dest_frame are
    // equal to the dimensions of the current image's dest_frame.
    CLIENT_FRAME_SCALE = 3;
    // The client should provide a new image produced by clipping the source image
    // to the region specified by src_frame.
    CLIENT_SRC_FRAME = 4;
    // The client should provide a new image produced by applying the desired
    // transformation, so that TRANSFORM_IDENTITY can be specified.
    CLIENT_TRANSFORM = 5;
    // The client should apply the color conversion itself.
    CLIENT_COLOR_CONVERSION = 6;
    // The client should apply the alpha itself.
    CLIENT_ALPHA = 7;
};

type ClientCompositionOp = struct {
    /// display_id and layer_id uniquely identify the subject of the
    /// opcode.
    display_id DisplayId;

    /// Invalid for issues that aren't scoped to a specific layer, such as
    /// unsupported color conversion tables.
    layer_id LayerId;

    opcode ClientCompositionOpcode;
};