Question

i got 2 dynamic texture ,and want add second texture color to first texture color But just where first texture color alpha is not 0
something like inverse transparncey
i add two pic link to show what is my mean:

TO

just collisions part must add two texture pixel color

ty for your help

Answer 1

just did it , works great

sampler circleSampler : register(s1);
sampler playerSampler : register(s0);

float4 main(float4 color : COLOR0 ,float2 texCoord : TEXCOORD0):COLOR0
{
float4 output = float4(1,1,1,1);
float4 CircColor = tex2D(circleSampler,texCoord);
float4 playerColor = tex2D(playerSampler,texCoord);
if (CircColor.a ==0)
{
output = playerColor;
}
else
{
output = CircColor* playerColor;
}
output.a = playerColor.a;
return output;
}

technique Technique1
{
    pass Pass1
    {

        PixelShader = compile ps_2_0 main();
    }
}

anyway ty for ur time