Bicubic Filtering Implementation for Custom Data Types

Implementing bicubic sampling for your custom `Data` struct can be a bit challenging, but let’s break it down into manageable steps.

Understanding Bicubic Interpolation

Bicubic interpolation uses a weighted average of a 4×4 grid of pixels surrounding the target pixel. The weights are calculated based on the distances from the target pixel to each pixel in the grid. Here’s how you can start:

Step 1: Create a Weight Calculation Function

You need a function that computes the weights based on the relative distances. The general formula for bicubic weights is based on the cubic Hermite polynomials.

    float CubicWeight(float t) {
        if (t < 0) t = -t;
        if (t < 1) return (1.0f - 2.0f * t * t + t * t * t);
        if (t < 2) return (4.0f - 8.0f * t + 5.0f * t * t - t * t * t);
        return 0.0f;
    }
    

Step 2: Implement the Bicubic Sampling Function

Your function will take a texture coordinate and use it to find the relevant textures. You'll need to fetch 16 neighboring pixels (assuming you have some way to access them as `Data` types).

    template <typename T>
    T TImage<T>::BicubicSampling(const Math::Vec2& texCoord) const {
        // Get integer coordinates of the 4x4 grid
        int x = static_cast(texCoord.x);
        int y = static_cast(texCoord.y);
        
        // Calculate fractional offsets
        float xDiff = texCoord.x - x;
        float yDiff = texCoord.y - y;

        // Create an array for weights
        Data results[4][4];
        float weights[4][4];
        
        // Fetch the neighbors and calculate weights
        for (int i = -1; i <= 2; ++i) {
            for (int j = -1; j <= 2; ++j) {
                // Get neighbors here (be sure to handle texture edges)
                results[i + 1][j + 1] = GetTextureData(x + i, y + j); 
                weights[i + 1][j + 1] = CubicWeight(i - xDiff) * CubicWeight(j - yDiff);
            }
        }
        
        // Now perform the weighted average
        Data finalResult;
        float totalWeight = 0.0f;
        
        for (int i = 0; i < 4; ++i) {
            for (int j = 0; j < 4; ++j) {
                finalResult = finalResult + results[i][j] * weights[i][j];
                totalWeight += weights[i][j];
            }
        }
        
        // Normalize the result
        if (totalWeight > 0) {
            finalResult = finalResult * (1.0f / totalWeight);
        }
        
        return finalResult;
    }
    

Step 3: Edge Case Handling

Make sure your `GetTextureData` function properly handles edge cases, so you don't access out-of-bounds data in texture grids.

Conclusion

This is a basic outline of how to implement bicubic sampling for your `Data` struct. The key parts are calculating the weights and making sure to handle the additional complexity of arbitrary data types correctly. Test thoroughly and refine based on your needs!

It sounds super frustrating to deal with that kind of inconsistency between two identical machines. Here are a few things you might want to try or check:

• Check the Windows Features: Sometimes, specific features or components in Windows can have unexpected restrictions or configurations. Make sure that both machines have the same Windows features enabled.
• Look at Device Manager: Even if the hardware is the same, check if there are any driver issues or differences in settings in Device Manager. Sometimes, one machine might have a newer or older driver installed.
• Environmental Variables: There might be path issues or environmental variable differences between the two systems. It could be worth looking into them to see if there’s anything that stands out.
• Check for Conflicting Software: Sometimes, other software can interfere. Check if there’s anything running on the machine where it’s failing that could be causing issues, like game-related overlays or different input software.
• Isolate the Problem: Try creating a very minimal application that uses `GameInputCreate` with no other dependencies to see if it still throws the same error. This could help identify if it’s something in the broader project setup or just specific to the GameInput API calls.

If you haven’t already, you might also want to dig into the Event Viewer for any related logs or errors that might give you more context. Good luck, and I hope you get it sorted out!

Wow, that shader code segment is definitely a head-scratcher, especially line 60! It seems really strange to use iadd with such a massive float value.

From my understanding, iadd is intended for integer addition, while the number you found, which fits as a float, implies some type of conversion is happening under the hood. It’s like the shader is taking a float representation of that large number but then treating it as an integer for the operation.

Considering the value you found in the bytecode (f8800000), it would actually represent a very different number if interpreted as an integer. It’s likely that the large negative value is just a way to introduce a specific adjustment in your calculations without worrying about what type of data it originally was.

For converting to HLSL, you might need to consider the asint() operation or maybe something like asuint() dependent on how that shader expects data. The sign is tricky because you’re working with a float and an integer in one go. If you end up with a float like 4.16914E+09, it’s hinting at something possibly going wrong. NaNs and INFs can definitely pop up with mismanaged types or unexpected value ranges.

Maybe it’s worth leaving that line as-is unless you see it breaking something downstream. Debugging shader code feels like a dark tunnel sometimes, and sometimes those oddities are just how things are designed to work. If you figure it out, I’d love to hear how!