imageWrite

pub fn imageWrite(
    image: anytype,
    T: type,
    coordinate: ImageCoordinate(std.meta.Child(@TypeOf(image)), T),
    texel: @Vector(4, ImageSampledType(std.meta.Child(@TypeOf(image)))),
) void

File

Code

pub fn imageWrite(
    image: anytype,
    T: type,
    coordinate: ImageCoordinate(std.meta.Child(@TypeOf(image)), T),
    texel: @Vector(4, ImageSampledType(std.meta.Child(@TypeOf(image)))),
) void {
    switch (T) {
        u32, i32 => {},
        f32 => if (builtin.target.os.tag != .opencl) {
            @compileError("Floating point image coordinates only supported by OpenCL");
        },
        else => @compileError("Expected one of u32, i32 and f32 types. Found '" ++ @typeName(T) ++ "'"),
    }

    const Image = switch (@typeInfo(@TypeOf(image))) {
        .pointer => |pointer| pointer.child,
        else => @compileError("Expected a pointer to SPIR-V image type, found '" ++ @typeName(@TypeOf(image)) ++ "'"),
    };

    const image_info = switch (@typeInfo(Image)) {
        .spirv => |spirv| switch (spirv) {
            .image => |info| info,
            else => @compileError("Expected SPIR-V image type, found '" ++ @typeName(Image) ++ "'"),
        },
        else => @compileError("Expected SPIR-V image type, found '" ++ @typeName(Image) ++ "'"),
    };

    switch (image_info.usage) {
        .unknown, .storage => {},
        else => @compileError("SPIR-V image must have unknown or storage usage"),
    }

    // TODO: If SubpassData dim is added, throw a compiler error if the image is arrayed and has the SubpassData dim.

    return asm volatile (
        \\%loaded_image = OpLoad %Image %image
        \\                OpImageWrite %loaded_image %coordinate %texel
        :
        : [Image] "t" (Image),
          [image] "" (image),
          [coordinate] "" (coordinate),
          [texel] "" (texel),
    );
}