Improved shields shader

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

@@ -9,32 +9,52 @@ uniform vec2 impact;
 uniform float impact_tick;
 uniform float impact_time;
 uniform float llpow;
+uniform float ellipsoidalFactor; //1 is perfect circle, >1 is ellipsoidal
+uniform float oscillationSpeed; //oscillation between ellipsoidal and spherical form
+float antialiasingRadius = 0.98; //1.0 is no antialiasing, 0.0 - fully smoothed(looks worse)
 
 void main(void)
 {
 	vec2 uv = vec2(0.5, 0.5) - gl_TexCoord[0].xy;
-	float l = length(uv) * 2.0;
-	float ll = pow(l, llpow);
-
-	vec4 c1 = texture2D(tex, (uv * ll / 1.3 + vec2(tick / time_factor, 0.0)));
-	vec4 c2 = texture2D(tex, (uv * ll / 1.3 + vec2(0.0, tick / time_factor)));
+	//uv.x *= ellispoidalFactor; //for simple ellipsoid
+	//comment next line for regular spherical shield
+	uv.x *= (1.0 + ellipsoidalFactor) * 0.5 + (ellipsoidalFactor - 1.0) * 0.5 * pow(cos(tick / time_factor * oscillationSpeed), 2.0);
+	float uvLen = length(uv);
+	
+	float antialiasingCoef = 1.0;
+	
+	float hordeLen = uvLen * 2.0;
+	if(hordeLen > 1.0)
+	{
+		gl_FragColor = vec4(0.0, 0.0, 0.0, 0.0);
+		return;
+	}else
+	{
+		if(hordeLen > antialiasingRadius)
+		{
+			antialiasingCoef = (1.0 - hordeLen) / (1.0 - antialiasingRadius);
+		}
+		hordeLen = asin(length(uv) * 2.0);
+	}
+	vec2 sphericalProjectedCoord = vec2(0.5, 0.5) + uv * (hordeLen / (3.141592 / 2.0)) / uvLen;
+	
+	vec4 c1 = texture2D(tex, (sphericalProjectedCoord + vec2(tick / time_factor, 0.0)));
+	vec4 c2 = texture2D(tex, (sphericalProjectedCoord + vec2(0.0, tick / time_factor)));
 	vec4 c = c1 * c2;
 
-	float dist = max(min(1.0, 1.0 - l), 0.0) * 3.0;
-	c.a *= c.a * dist;
+	float transperency = 1.0 - exp(-0.07f / cos(hordeLen));
+	
+	c.a = c.a * transperency;
 
-	float z = l;
-	c.a *= z;
 
-	if (l > 1.0) c.a = 0.0;
-	if (l < 0.5) {
-		c.a *= ll * 4.0;
-	}
 
 	// Impact
 	float it = tick - impact_tick;
 	float vaadjust = aadjust;
 	if (it < impact_time) {
+		float l = uvLen * 2.0;
+		float ll = pow(l, llpow);
+
 		float v = (impact_time - it) / impact_time;
 		float il = distance(impact / ll, (vec2(0.5) - gl_TexCoord[0].xy) / ll);
 		if (il < 0.5 * (1.0 - v)) {
@@ -46,9 +66,9 @@ void main(void)
 	}
 
 	c.a *= vaadjust;
+	c.rgb *= color;
 
-	if (l <= 1.0) c.a = max(0.15, c.a);
+	c.a *= min(1.0, c.a) * antialiasingCoef;
 
-	c.rgb *= color;
 	gl_FragColor = c;
 }

game/modules/tome/data/gfx/shaders/shield.lua

@@ -29,8 +29,10 @@ return {
 		impact = {0, 0},
 		impact_tick = -1000,
 		impact_color = {1.0, 0.3, 1.0},
-		impact_time = 400,
+		impact_time = 800,
 		llpow = 2,
+		ellipsoidalFactor = ellipsoidalFactor or 1.2,
+		oscillationSpeed = oscillationSpeed or 0,
 	},
 	clone = false,
 }