public void setTextureAlpha(float alpha) {
if (mTextureAlpha == alpha) return;
mTextureAlpha = alpha;
if (alpha >= OPAQUE_ALPHA) {
// The alpha is need for those texture without alpha channel
mGL.glColor4f(1, 1, 1, 1);
setTexEnvMode(GL11.GL_REPLACE);
} else {
mGL.glColor4f(alpha, alpha, alpha, alpha);
setTexEnvMode(GL11.GL_MODULATE);
}
}
private void setAlphaValue(float alpha) {
if (mLastAlpha == alpha) return;
GL11 gl = mGL;
mLastAlpha = alpha;
if (alpha >= 0.95f) {
gl.glTexEnvf(GL11.GL_TEXTURE_ENV, GL11.GL_TEXTURE_ENV_MODE, GL11.GL_REPLACE);
} else {
gl.glTexEnvf(GL11.GL_TEXTURE_ENV, GL11.GL_TEXTURE_ENV_MODE, GL11.GL_MODULATE);
gl.glColor4f(alpha, alpha, alpha, alpha);
}
}
public void drawColor(int x, int y, int width, int height, int color) {
float alpha = mTransformation.getAlpha();
GL11 gl = mGL;
if (mTexture2DEnabled) {
// Set mLastAlpha to an invalid value, so that it will reset again
// in setAlphaValue(float) later.
mLastAlpha = -1.0f;
gl.glDisable(GL11.GL_TEXTURE_2D);
mTexture2DEnabled = false;
}
alpha /= 256.0f;
gl.glColor4f(
Color.red(color) * alpha,
Color.green(color) * alpha,
Color.blue(color) * alpha,
Color.alpha(color) * alpha);
drawRect(x, y, width, height);
}