Semi-Transparent Texture2D by shader

Graphics
1

Hi,
can I make semi-transparent texture(Texture2D) by using shaders? I found another way to do this(by multiplying color parameter in draw method) but i really want to use(and learn how to use) shaders. Or maybe i miss understanding how and for what use shaders?

2

Changing the color is something a shader could do, but for this you may as well just use the color parameter.
There is an overhead to switching shader, and if your current shader already supports per vertex color (the default sprite shader does) then you should just keep using it and set the color.

3

Ok, i will do it by multiplying color, but shaders are still in my mind. All day i read about it, and i want use way where shader file(fx) are compiled to xnb file but i don’t know how to use MGCB.exe program. I know that it is console application with inline input parameters, but i don’t know what parameters i should put(wiki page describe realy basic stuff). When i try use Pipeline.exe application(from “night build”) xnb file is incompatible with my mono 3.2 stable version(error: Wrong MGFX file version!) I try make very simple shader(basically swapping the color to red).

4

Ok, I did it, i created my first custom shader. It was difficult, hlsl language is a little strange(intellisense doesn’t work)but for future seekers i try answer to my last question:
Bellow simple cmd command that convert fx file to xnb by MGCB.exe

C:\Program Files (x86)\MSBuild\MonoGame\v3.0\MGCB>MGCB.exe /importer:EffectImporter /processor:EffectProcessor /build:path\to\fx\file\Effect1.fx

and bellow simple shader that is compatible with windows phone 8 and monogame 3.2

sampler TextureSampler : register(s0);

float4 PixelShaderFunction(float4 position : SV_Position, float4 color : COLOR0, float2 texCoord : TEXCOORD0) : COLOR0
{
    float4 tex = tex2D(TextureSampler, texCoord);
    return tex;
}


technique Technique1
{
    pass Pass1
    {
        PixelShader = compile ps_4_0_level_9_1 PixelShaderFunction();
    }
}

I recommend also read this threads: