capturePng

Captures one frame and return the png data for that frame.

Captures the physical pixels in rect, or if null the entire OS window.

The returned data is allocated by Self.allocator and should be freed by the caller.

Parameters

frame:dvui.App.frameFunction: dvui.App.frameFunction
rect:?dvui.Rect.Physical: ?dvui.Rect.Physical
writer:*std.Io.Writer: *std.Io.Writer

Source

Implementation

pub fn capturePng(frame: dvui.App.frameFunction, rect: ?dvui.Rect.Physical, writer: *std.Io.Writer) !void {
    var picture = dvui.Picture.start(rect orelse dvui.windowRectPixels()) orelse {
        std.debug.print("Current backend does not support capturing images\n", .{});
        return error.Unsupported;
    };

    // run the gui code
    if (try frame() == .close) return error.closed;

    // render the retained dialogs and deferred renders
    _ = dvui.currentWindow().endRendering(.{});

    picture.stop();

    // texture will be destroyed in picture.deinit() so grab pixels now
    try picture.png(writer);

    // draw texture and destroy
    picture.deinit();

    const cw = dvui.currentWindow();

    _ = try cw.end(.{});
    try cw.begin(cw.frame_time_ns + 100 * std.time.ns_per_ms);
}