Irrlicht Engine

I add the shader material:

gpu->addHighLevelShaderMaterialFromFiles(
G_XFXBASE, "VS", video::EVST_VS_2_0,
G_XFXBASE, "PS", video::EPST_PS_2_0,
baseShaderAlphaInst, video::EMT_TRANSPARENT_ALPHA_CHANNEL);

Code in the shader to set the alpha value:

struct VSOut
{
float4 pos : POSITION0 ...

hello!
I have a problem with a material. I created a hlsl shader material based on the material EMT_TRANSPARENT_ALPHA_CHANNEL. Within the shader I set the alpha value of the output color to a static value between 0 and 1. The problem is that sometimes you can see through the surface rendered with ...