update shadows

res/shaders/lib/shadows.glsl

@@ -15,23 +15,26 @@ float calc_shadow() {
     float step = 1.0 / float(u_shadowsRes);
     float s = pow(abs(cos(u_dayTime * PI2)), 0.25) * u_shadowsOpacity;
     vec3 normalOffset = a_realnormal * (a_distance > 64.0 ? 0.2 : 0.04);
-    int shadowIdx = a_distance > 64.0 ? 1 : 0;
+    int shadowIdx = a_distance > 80.0 ? 1 : 0;
 
     vec4 mpos = u_shadowsMatrix[shadowIdx] * vec4(a_modelpos.xyz + normalOffset, 1.0);
     vec3 projCoords = mpos.xyz / mpos.w;
     projCoords = projCoords * 0.5 + 0.5;
-    projCoords.z -= 0.00001;
+    projCoords.z -= 0.00001 / u_shadowsRes;
+    if (shadowIdx > 0) {
+        projCoords.z -= 0.001;
+    }
 
     float shadow = 0.0;
     if (dot(a_realnormal, u_sunDir) < 0.0) {
-        // 5x5 kernel
-        for (int y = -2; y <= 2; y++) {
-            for (int x = -2; x <= 2; x++) {
-                vec3 offset = vec3(x, y, -(abs(x) + abs(y)) * 0.1) * step * 2.0 * u_shadowsSoftness;
+        // 3x3 kernel
+        for (int y = -1; y <= 1; y++) {
+            for (int x = -1; x <= 1; x++) {
+                vec3 offset = vec3(x, y, -(abs(x) + abs(y)) * 0.8) * step * 1.0 * u_shadowsSoftness;
                 shadow += texture(u_shadows[shadowIdx], projCoords + offset);
             }
         }
-        shadow /= 25.0;
+        shadow /= 9.0;
     } else {
         shadow = 0.5;
     }