Get height value from virtual heightfield mesh MinMax texture? C++

Development Programming & Scripting
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1

I read somwhere in the comments of a ue5 tut that “Heightfield MinMax textures seem to be the heightmap encoded in DXT1 RG containing the differences (MinMax) B Height encoded with DXT1 artifacts.” Don’t know if that is true, though tried to read height values from the said texture at a given location , the values are returning null/zero! Here’s the piece of code:

#include "HeightValueFromTexture.h"
#include "Engine/Texture2D.h"
#include "RenderUtils.h"

float UHeightValueFromTexture::UHeightValueFromTexture::GetHeightValueFromTexture(UTexture2D* Texture, FVector WorldLocation, FVector2D WorldSizeXY)

{
    if (!Texture)
    {
        return 0.0f;
    }

    int32 Width = Texture->GetSizeX();
    int32 Height = Texture->GetSizeY();

    // Convert world location to UV space
    float U = FMath::Clamp((WorldLocation.X / WorldSizeXY.X), 0.0f, 1.0f);
    float V = FMath::Clamp((WorldLocation.Y / WorldSizeXY.Y), 0.0f, 1.0f);

    int32 X = FMath::Clamp<int32>(FMath::RoundToInt(U * Width), 0, Width - 1);
    int32 Y = FMath::Clamp<int32>(FMath::RoundToInt(V * Height), 0, Height - 1);

    FColor* FormattedImageData = static_cast<FColor*>(Texture->PlatformData->Mips[0].BulkData.Lock(LOCK_READ_ONLY));
    if (!FormattedImageData)
    {
        return 0.0f;
    }

    FColor PixelColor = FormattedImageData[X + Y * Width];
    float MinHeight = PixelColor.R / 255.0f;
    float MaxHeight = PixelColor.G / 255.0f;
    float NormalizedHeightValue = PixelColor.B / 255.0f;

    Texture->PlatformData->Mips[0].BulkData.Unlock();

    // Calculate the height range
    float HeightRange = MaxHeight - MinHeight;

    // Convert the normalized height value to world units using the height range
    float WorldHeightValue = MinHeight + (NormalizedHeightValue * HeightRange);

    
    return WorldHeightValue;
}