When in underwater levels the screen will very slightly .. hum .. wooble

game/modules/tome/class/Player.lua

@@ -405,6 +405,11 @@ function _M:updateMainShader()
 		elseif game.level and game.level.data and game.level.data.motionblur then game.fbo_shader:setUniform("motionblur", game.level.data.motionblur)
 		else game.fbo_shader:setUniform("motionblur", 0) -- Disable
 		end
+
+		-- Underwater shader
+		if game.level and game.level.data and game.level.data.underwater then game.fbo_shader:setUniform("underwater", 1)
+		else game.fbo_shader:setUniform("underwater", 0) -- Disable
+		end
 	end
 end
 

game/modules/tome/data/gfx/shaders/main_fbo.frag

@@ -3,6 +3,7 @@ uniform float air_warning;
 uniform float death_warning;
 uniform float solipsism_warning;
 uniform float motionblur;
+uniform float underwater;
 uniform float blur;
 uniform float tick;
 uniform sampler2D noisevol;
@@ -11,6 +12,61 @@ uniform sampler2D tex;
 uniform vec4 colorize;
 uniform vec4 intensify;
 
+// Simple Water shader. (c) Victor Korsun, bitekas@gmail.com; 2012.
+//
+// Attribution-ShareAlike CC License.
+
+#ifdef GL_ES
+precision highp float;
+#endif
+
+uniform vec2 mapCoord;
+
+const float PI = 3.1415926535897932;
+
+// play with these parameters to custimize the effect
+// ===================================================
+
+//speed
+const float speed = 0.05;
+const float speed_x = 0.3;
+const float speed_y = 0.3;
+
+// refraction
+const float emboss = 0.05;
+const float intensity = 0.4;
+const int steps = 6;
+const float frequency = 100.0;
+const int angle = 7; // better when a prime
+
+// reflection
+const float delta = 60.;
+const float intence = 700.;
+
+const float reflectionCutOff = 0.012;
+const float reflectionIntence = 200000.;
+
+// ===================================================
+
+float time = tick / 30000.0;
+
+float col(vec2 coord)
+{
+	float delta_theta = 2.0 * PI / float(angle);
+	float col = 0.0;
+	float theta = 0.0;
+	for (int i = 0; i < steps; i++)
+	{
+		vec2 adjc = coord;
+		theta = delta_theta*float(i);
+		adjc.x += cos(theta)*time*speed + time * speed_x;
+		adjc.y -= sin(theta)*time*speed - time * speed_y;
+		col = col + cos( (adjc.x*cos(theta) - adjc.y*sin(theta))*frequency)*intensity;
+	}
+
+	return cos(col);
+}
+
 void main(void)
 {
 	gl_FragColor = texture2D(tex, gl_TexCoord[0].xy);
@@ -96,6 +152,30 @@ void main(void)
 		sample /= (blur*2.0) * (blur*2.0);
 		gl_FragColor = sample;
 	}
+	else if (underwater > 0.0)
+	{
+		vec2 p = (vec2(gl_FragCoord.x - mapCoord.x, texSize.y - gl_FragCoord.y - mapCoord.y)) / texSize.xy, c1 = p, c2 = p;
+		float cc1 = col(c1);
+
+		c2.x += texSize.x/delta;
+		float dx = emboss*(cc1-col(c2))/delta;
+
+		c2.x = p.x;
+		c2.y += texSize.y/delta;
+		float dy = emboss*(cc1-col(c2))/delta;
+
+		c1.x += dx*2.;
+		c1.y = -(c1.y+dy*2.);
+
+		float alpha = 1.+dot(dx,dy)*intence;
+			
+		float ddx = dx - reflectionCutOff;
+		float ddy = dy - reflectionCutOff;
+		if (ddx > 0. && ddy > 0.) alpha = pow(alpha, ddx*ddy*reflectionIntence);
+			
+		vec4 col = texture2D(tex,c1)*(alpha);
+		gl_FragColor = col;
+	}
 
 	if (colorize.r > 0.0 || colorize.g > 0.0 || colorize.b > 0.0)
 	{

game/modules/tome/data/zones/flooded-cave/zone.lua

@@ -27,6 +27,7 @@ return {
 	width = 70, height = 70,
 --	all_remembered = true,
 	all_lited = true,
+	underwater = true,
 	persistent = "zone",
 	ambient_music = "Inside a dream.ogg",
 	-- Apply a bluish tint to all the map

game/modules/tome/data/zones/lake-nur/zone.lua

@@ -84,6 +84,7 @@ return {
 			},
 		},
 		[2] = {
+			underwater = true,
 			generator = {
 				actor = {
 					filters = {{special_rarity="water_rarity"}},
@@ -91,6 +92,7 @@ return {
 			},
 		},
 		[3] = {
+			underwater = is_flooded,
 			generator = is_flooded and {
 				map = {
 					down = "SHERTUL_FORTRESS",

game/modules/tome/data/zones/temple-of-creation/zone.lua

@@ -26,6 +26,7 @@ return {
 	width = 70, height = 70,
 --	all_remembered = true,
 --	all_lited = true,
+	underwater = true,
 	persistent = "zone",
 	ambient_music = "Inside a dream.ogg",
 	-- Apply a bluish tint to all the map