add fog_curve parameter & update shaders

res/presets/weather/rain.json

@@ -16,5 +16,6 @@
     },
     "fog_opacity": 0.8,
     "fog_dencity": 2.0,
+    "fog_curve": 0.5,
     "clouds": 0.5
 }

res/shaders/entity.glslf

@@ -1,7 +1,7 @@
 in vec4 a_color;
 in vec2 a_texCoord;
-in float a_distance;
 in vec3 a_dir;
+in float a_fog;
 out vec4 f_color;
 
 uniform sampler2D u_texture0;
@@ -14,12 +14,10 @@ uniform bool u_alphaClip;
 void main() {
     vec3 fogColor = texture(u_cubemap, a_dir).rgb;
     vec4 tex_color = texture(u_texture0, a_texCoord);
-    float depth = (a_distance/256.0);
     float alpha = a_color.a * tex_color.a;
     // anyway it's any alpha-test alternative required
     if (alpha < (u_alphaClip ? 0.5f : 0.15f))
         discard;
-    f_color = mix(a_color * tex_color, vec4(fogColor,1.0), 
-              min(1.0, pow(depth*u_fogFactor, u_fogCurve)));
+    f_color = mix(a_color * tex_color, vec4(fogColor,1.0), a_fog);
     f_color.a = alpha;
 }

res/shaders/entity.glslv

@@ -7,7 +7,7 @@ layout (location = 3) in float v_light;
 
 out vec4 a_color;
 out vec2 a_texCoord;
-out float a_distance;
+out float a_fog;
 out vec3 a_dir;
 
 uniform mat4 u_model;
@@ -16,6 +16,11 @@ uniform mat4 u_view;
 uniform vec3 u_cameraPos;
 uniform float u_gamma;
 uniform float u_opacity;
+uniform float u_fogFactor;
+uniform float u_fogCurve;
+uniform float u_weatherFogOpacity;
+uniform float u_weatherFogDencity;
+uniform float u_weatherFogCurve;
 uniform samplerCube u_cubemap;
 
 uniform vec3 u_torchlightColor;
@@ -38,6 +43,10 @@ void main() {
     vec3 skyLightColor = pick_sky_color(u_cubemap);
     a_color.rgb = max(a_color.rgb, skyLightColor.rgb*decomp_light.a) * v_color;
     a_color.a = u_opacity;
-    a_distance = length(u_view * u_model * vec4(pos3d * FOG_POS_SCALE, 0.0));
+
+    float dist = length(u_view * u_model * vec4(pos3d * FOG_POS_SCALE, 0.0));
+    float depth = (dist / 256.0);
+    a_fog = min(1.0, max(pow(depth * u_fogFactor, u_fogCurve),
+                         min(pow(depth * u_weatherFogDencity, u_weatherFogCurve), u_weatherFogOpacity)));
     gl_Position = u_proj * u_view * modelpos;
 }

res/shaders/main.glslf

@@ -1,13 +1,11 @@
 in vec4 a_color;
 in vec2 a_texCoord;
-in float a_distance;
 in float a_fog;
 in vec3 a_dir;
 out vec4 f_color;
 
 uniform sampler2D u_texture0;
 uniform samplerCube u_cubemap;
-uniform vec3 u_fogColor;
 uniform bool u_alphaClip;
 
 void main() {

res/shaders/main.glslv

@@ -19,6 +19,8 @@ uniform float u_fogFactor;
 uniform float u_fogCurve;
 uniform float u_weatherFogOpacity;
 uniform float u_weatherFogDencity;
+uniform float u_weatherFogCurve;
+uniform float u_timer;
 uniform samplerCube u_cubemap;
 
 uniform vec3 u_torchlightColor;
@@ -44,6 +46,6 @@ void main() {
     a_distance = length(u_view * u_model * vec4(pos3d * FOG_POS_SCALE, 0.0));
     float depth = (a_distance / 256.0);
     a_fog = min(1.0, max(pow(depth * u_fogFactor, u_fogCurve),
-                         min(depth * u_weatherFogDencity, u_weatherFogOpacity)));
+                         min(pow(depth * u_weatherFogDencity, u_weatherFogCurve), u_weatherFogOpacity)));
     gl_Position = u_proj * u_view * modelpos;
 }