Add option to use texture alpha channel

client/shaders/test_shader_3/base.txt

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+trans_alphach

client/shaders/test_shader_3/opengl_fragment.glsl

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+
+uniform sampler2D myTexture;
+uniform float fogDistance;
+
+varying vec3 vPosition;
+
+void main (void)
+{
+	vec4 col = texture2D(myTexture, vec2(gl_TexCoord[0]));
+	col *= gl_Color;
+	col = col * col; // SRGB -> Linear
+	col *= 1.8;
+	col.r = 1.0 - exp(1.0 - col.r) / exp(1.0);
+	col.g = 1.0 - exp(1.0 - col.g) / exp(1.0);
+	col.b = 1.0 - exp(1.0 - col.b) / exp(1.0);
+	col = sqrt(col); // Linear -> SRGB
+	float a = col.a;
+	if(fogDistance != 0.0){
+		float d = max(0.0, min(vPosition.z / fogDistance * 1.5 - 0.6, 1.0));
+		a = mix(a, 0.0, d);
+	}
+	gl_FragColor = vec4(col.r, col.g, col.b, a);
+}

client/shaders/test_shader_3/opengl_vertex.glsl

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+
+uniform mat4 mWorldViewProj;
+uniform mat4 mInvWorld;
+uniform mat4 mTransWorld;
+uniform float dayNightRatio;
+
+varying vec3 vPosition;
+
+void main(void)
+{
+	gl_Position = mWorldViewProj * gl_Vertex;
+
+	vPosition = (mWorldViewProj * gl_Vertex).xyz;
+
+	vec4 color;
+	//color = vec4(1.0, 1.0, 1.0, 1.0);
+
+	float day = gl_Color.r;
+	float night = gl_Color.g;
+	float light_source = gl_Color.b;
+
+	/*color.r = mix(night, day, dayNightRatio);
+	color.g = color.r;
+	color.b = color.r;*/
+
+	float rg = mix(night, day, dayNightRatio);
+	rg += light_source * 1.0; // Make light sources brighter
+	float b = rg;
+
+	// Moonlight is blue
+	b += (day - night) / 13.0;
+	rg -= (day - night) / 13.0;
+
+	// Emphase blue a bit in darker places
+	// See C++ implementation in mapblock_mesh.cpp finalColorBlend()
+	b += max(0.0, (1.0 - abs(b - 0.13)/0.17) * 0.025);
+
+	// Artificial light is yellow-ish
+	// See C++ implementation in mapblock_mesh.cpp finalColorBlend()
+	rg += max(0.0, (1.0 - abs(rg - 0.85)/0.15) * 0.065);
+
+	color.r = rg;
+	color.g = rg;
+	color.b = b;
+
+	color.a = gl_Color.a;
+
+	gl_FrontColor = gl_BackColor = color;
+
+	gl_TexCoord[0] = gl_MultiTexCoord0;
+}