Disable bilinear filtering for Image

[ThisIsRex]

I want to display a small image or a pixel art so I don't need an antialiasing. How to disable it for specific widget?
Image::new(image::Handle::from_pixels(3, 3, img_data)) .width(Length::Units(100)) .height(Length::Units(100))

[twitchyliquid64]

Images (on desktop) aren't processed in any way - they are rastered to a texture, uploaded to the GPU, and drawn.

If your input image is 3 pixels in size, but you are rendering it in a 100x100 pixel area, you are probably running into texture sampling. Our image pipline has these settings:

let sampler = device.create_sampler(&wgpu::SamplerDescriptor {
            address_mode_u: wgpu::AddressMode::ClampToEdge,
            address_mode_v: wgpu::AddressMode::ClampToEdge,
            address_mode_w: wgpu::AddressMode::ClampToEdge,
            mag_filter: wgpu::FilterMode::Linear,
            min_filter: wgpu::FilterMode::Linear,
            mipmap_filter: wgpu::FilterMode::Linear,
            ..Default::default()
        });

LINEAR indicates that adjacent pixels are linearly interpolated, resulting in a smooth fade. I think thats probably the cause of your issues, if you want abrupt/blocky changes for pixel art. Unfortunately KhronosGroup/Vulkan-Docs#1361 suggests that NEAREST has inconsistent behavior across GPUs, so I'm not sure if exposing a different mode here is a good option.

Not ideal, but would it be possible to scale up the image to 100x100 instead of using a small image?

[ThisIsRex]

Not ideal, but would it be possible to scale up the image to 100x100 instead of using a small image?

I want to make a program which should representante binary data as image, like a hex editor, but with pixels instead of numbers and the canvas might be small

[twitchyliquid64]

Unfortunately sampler behavior is a core part of the image pipeline and cannot be easily switched over for some primitives. It might be possible to have a second sampler that we switch to for such images, but as I'm no expert with the wgpu stuff and this would be a pretty core change, I'll leave that to @hecrj to opine on.

In the absence of any new features or code changes to iced, I think scaling up your pixel art to the size of the image widget is the best path forward.

[hecrj]

@ThisIsRex Have you considered using a Canvas widget to draw your pixel art using rectangles instead of generating a bitmap? Would that be overkill? How many pixels are we talking about?

[ThisIsRex]

@ThisIsRex Have you considered using a Canvas widget to draw your pixel art using rectangles instead of generating a bitmap? Would that be overkill? How many pixels are we talking about?

I want to make a program, which should visualize any binary file as pixels. The image size can be various, from 3x3 to 2048x2048 with zooming. I think, Canvas is not the best widget for doing this.

[ronvoluted]

@ThisIsRex Would SVG rects work for your case? It would preserve 'pixel'/square separation but this remark in the docs suggests it should be benchmarked:

"Svg images can have a considerable rendering cost when resized, specially when they are complex."
https://docs.rs/iced/0.1.1/iced/widget/svg/struct.Svg.html

[bluecheetah001]

the KhronosGroup/Vulkan-Docs#1361 link is just saying that nearest isn't guaranteed when anisotrophy is enabled. but anisotrophy shouldn't be needed for UI graphics that always render head-on.

[Mingun]

but anisotrophy shouldn't be needed for UI graphics that always render head-on.

Note: that could not be true if you want UI like in Dead Space (spoiler: all UI in game is "in-game" literally)