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[PompiPompi]

I am using the fixed pipline of OpenGLES for my Android game.
I am using it to draw sprites.
I was able to blend my sprite with a color, for effects like getting hurt(sprites is tinted with red).
However, I was not able to change the sprite's overall alpha in order to make it transparent.
The sprite's texture alpha channel does make it transparent where it's not 1. I just want to "tint" the alpha with a constant alpha. So for instance a constant 0.5 alpha would make the sprite 50% transparent(over what it already has).

My code for making the color tinting is:

Code:

c[0] = (float)((int)((Color/0x10000)%0x100))/(float)0xFF;
c[1] = (float)((int)(Color/0x100)%0x100)/(float)0xFF;
c[2] = (float)(Color%0x100)/(float)0xFF;
c[3] = (float)((int)((Color/0x1000000)%0x100))/(float)0xFF;
gl.glTexEnvf(gl.GL_TEXTURE_ENV, gl.GL_TEXTURE_ENV_MODE, gl.GL_BLEND );
gl.glTexEnvfv(gl.GL_TEXTURE_ENV, gl.GL_TEXTURE_ENV_COLOR, c, 0);

I can't figure how to make the transparency tinting.

Thanks.

[Maud'Dib Atreides]

gl.glBlendFunc(GL10.GL_SRC_ALPHA, GL10.GL_ONE_MINUS_SRC_ALPHA);

You should totally try this line of code.

Regarded these are PNG's

[PompiPompi]

Oh, this is what I did(what you suggested only referes to blending with the backbuffer)

Code:

if(gl instanceof GL11)
{
GL11 gl11 = (GL11)gl;
gl11.glTexEnvi(GL11.GL_TEXTURE_ENV, GL11.GL_TEXTURE_ENV_MODE, GL11.GL_COMBINE);
//Sample RGB, multiply by previous texunit result
gl11.glTexEnvi(GL11.GL_TEXTURE_ENV, GL11.GL_COMBINE_RGB, GL11.GL_MODULATE);   //Modulate RGB with RGB
gl11.glTexEnvi(GL11.GL_TEXTURE_ENV, GL11.GL_SRC0_RGB, GL11.GL_CONSTANT);
gl11.glTexEnvi(GL11.GL_TEXTURE_ENV, GL11.GL_SRC1_RGB, GL11.GL_TEXTURE);
gl11.glTexEnvi(GL11.GL_TEXTURE_ENV, GL11.GL_OPERAND0_RGB, GL11.GL_SRC_COLOR);
gl11.glTexEnvi(GL11.GL_TEXTURE_ENV, GL11.GL_OPERAND1_RGB, GL11.GL_SRC_COLOR);
//Sample ALPHA, multiply by previous texunit result
gl11.glTexEnvi(GL11.GL_TEXTURE_ENV, GL11.GL_COMBINE_ALPHA, GL11.GL_MODULATE);  //Modulate ALPHA with ALPHA
gl11.glTexEnvi(GL11.GL_TEXTURE_ENV, GL11.GL_SRC0_ALPHA, GL11.GL_CONSTANT);
gl11.glTexEnvi(GL11.GL_TEXTURE_ENV, GL11.GL_SRC1_ALPHA, GL11.GL_TEXTURE);
gl11.glTexEnvi(GL11.GL_TEXTURE_ENV, GL11.GL_OPERAND0_ALPHA, GL11.GL_SRC_ALPHA);
gl11.glTexEnvi(GL11.GL_TEXTURE_ENV, GL11.GL_OPERAND1_ALPHA, GL11.GL_SRC_ALPHA);
// gl.glTexEnvf(gl.GL_TEXTURE_ENV, ((GL11)gl).GL_COMBINE_ALPHA, ((GL11)gl).GL_MODULATE);
// gl.glTexEnvf(gl.GL_TEXTURE_ENV, ((GL11)gl).GL_ALPHA_SCALE, c[3]);
}