How can I tint a sprite to white in XNA?

Question

I don't think this is possible just using the color setting in SpriteBatch, so I'm trying to work out a simple shader that would take every pixel and make it white, while respecting the alpha value of the pixel.

The answer Joel Martinez gave looks right, but how do I incorporate that when I draw the sprite with SpriteBatch?

Answer 1

I think this is what you're looking for

sampler2D baseMap;

struct PS_INPUT 
{
   float2 Texcoord : TEXCOORD0;

};

float4 ps_main( PS_INPUT Input ) : COLOR0
{
   float4 color = tex2D( baseMap, Input.Texcoord );
   return float4(1.0f, 1.0f, 1.0f, color.w);
}

It's very simple, it just takes the sampled color from the texture, and then returns an all white color using the texture's alpha value.