Create/Update assets for version 1.13.2

assets/minecraft/shaders/program/bumpy.fsh

@@ -0,0 +1,34 @@
+#version 120
+
+uniform sampler2D DiffuseSampler;
+
+varying vec2 texCoord;
+varying vec2 oneTexel;
+
+void main(){
+    vec4 c = texture2D(DiffuseSampler, texCoord);
+    vec4 u = texture2D(DiffuseSampler, texCoord + vec2(        0.0, -oneTexel.y));
+    vec4 d = texture2D(DiffuseSampler, texCoord + vec2(        0.0,  oneTexel.y));
+    vec4 l = texture2D(DiffuseSampler, texCoord + vec2(-oneTexel.x,         0.0));
+    vec4 r = texture2D(DiffuseSampler, texCoord + vec2( oneTexel.x,         0.0));
+
+    vec4 nc = normalize(c);
+    vec4 nu = normalize(u);
+    vec4 nd = normalize(d);
+    vec4 nl = normalize(l);
+    vec4 nr = normalize(r);
+
+    float du = dot(nc, nu);
+    float dd = dot(nc, nd);
+    float dl = dot(nc, nl);
+    float dr = dot(nc, nr);
+
+    float i = 64.0;
+
+    float f = 1.0;
+    f += (du * i) - (dd * i);
+    f += (dr * i) - (dl * i);
+
+    vec4 color = c * clamp(f, 0.5, 2);
+    gl_FragColor = vec4(color.rgb, 1.0);
+}