Implement proper underwater vision for seaponies

src/main/java/com/minelittlepony/unicopia/client/render/WorldRenderDelegate.java

@@ -14,9 +14,11 @@ import com.minelittlepony.unicopia.entity.ItemImpl;
 import com.minelittlepony.unicopia.entity.Living;
 import com.minelittlepony.unicopia.entity.duck.LavaAffine;
 import com.minelittlepony.unicopia.entity.player.Pony;
+import com.mojang.blaze3d.systems.RenderSystem;
 
 import net.minecraft.client.MinecraftClient;
 import net.minecraft.client.render.*;
+import net.minecraft.client.render.BackgroundRenderer.FogType;
 import net.minecraft.client.render.VertexConsumerProvider.Immediate;
 import net.minecraft.client.util.math.MatrixStack;
 import net.minecraft.entity.*;
@@ -46,6 +48,15 @@ public class WorldRenderDelegate {
         return Optional.empty();
     }
 
+    public void applyFog(Camera camera, FogType fogType, float viewDistance, boolean thickFog, float tickDelta) {
+        if (camera.getSubmersionType() == CameraSubmersionType.WATER) {
+            if (EquinePredicates.PLAYER_SEAPONY.test(MinecraftClient.getInstance().player)) {
+                RenderSystem.setShaderFogStart(RenderSystem.getShaderFogStart() - 30);
+                RenderSystem.setShaderFogEnd(RenderSystem.getShaderFogEnd() + 190);
+            }
+        }
+    }
+
     public boolean beforeEntityRender(Entity entity,
             double x, double y, double z, float yaw,
             float tickDelta, MatrixStack matrices, VertexConsumerProvider vertices, int light) {

src/main/java/com/minelittlepony/unicopia/entity/player/PlayerCamera.java

@@ -3,11 +3,9 @@ package com.minelittlepony.unicopia.entity.player;
 import java.util.Optional;
 
 import com.minelittlepony.common.util.animation.MotionCompositor;
-import com.minelittlepony.unicopia.Race;
 import com.minelittlepony.unicopia.ability.magic.SpellPredicate;
 import com.minelittlepony.unicopia.ability.magic.spell.AbstractDisguiseSpell;
 
-import net.minecraft.client.render.CameraSubmersionType;
 import net.minecraft.util.math.Vec3d;
 
 public class PlayerCamera extends MotionCompositor {
@@ -61,15 +59,6 @@ public class PlayerCamera extends MotionCompositor {
             .map(d -> distance * d);
     }
 
-    public Optional<CameraSubmersionType> getSubmersionType(CameraSubmersionType original) {
-        if (player.getCompositeRace().includes(Race.SEAPONY)) {
-            if (original == CameraSubmersionType.WATER) {
-                return Optional.of(CameraSubmersionType.NONE);
-            }
-        }
-        return Optional.empty();
-    }
-
     public double calculateFieldOfView(double fov) {
         fov += player.getMagicalReserves().getExertion().get() / 5F;
         fov += getEnergyAddition();

src/main/java/com/minelittlepony/unicopia/mixin/client/MixinBackgroundRenderer.java

@@ -0,0 +1,20 @@
+package com.minelittlepony.unicopia.mixin.client;
+
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+
+import com.minelittlepony.unicopia.client.render.WorldRenderDelegate;
+
+import net.minecraft.client.render.BackgroundRenderer;
+import net.minecraft.client.render.Camera;
+import net.minecraft.client.render.BackgroundRenderer.FogType;
+
+@Mixin(BackgroundRenderer.class)
+abstract class MixinBackgroundRenderer {
+    @Inject(method = "applyFog", at = @At("RETURN"))
+    private static void onApplyFog(Camera camera, FogType fogType, float viewDistance, boolean thickFog, float tickDelta, CallbackInfo info) {
+        WorldRenderDelegate.INSTANCE.applyFog(camera, fogType, viewDistance, thickFog, tickDelta);
+    }
+}

src/main/java/com/minelittlepony/unicopia/mixin/client/MixinCamera.java

@@ -8,7 +8,6 @@ import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
 
 import com.minelittlepony.unicopia.client.UnicopiaClient;
 import net.minecraft.client.render.Camera;
-import net.minecraft.client.render.CameraSubmersionType;
 
 @Mixin(Camera.class)
 abstract class MixinCamera {
@@ -34,11 +33,4 @@ abstract class MixinCamera {
     private void redirectCameraDistance(double initial, CallbackInfoReturnable<Double> info) {
         UnicopiaClient.getCamera().flatMap(c -> c.calculateDistance(info.getReturnValueD())).ifPresent(info::setReturnValue);
     }
-
-    @Inject(method = "getSubmersionType",
-            at = @At("RETURN"),
-            cancellable = true)
-    public void getSubmersionType(CallbackInfoReturnable<CameraSubmersionType> info) {
-        UnicopiaClient.getCamera().flatMap(c -> c.getSubmersionType(info.getReturnValue())).ifPresent(info::setReturnValue);
-    }
 }

src/main/resources/unicopia.mixin.json

@@ -59,6 +59,7 @@
   "client": [
     "client.MixinAnimalModel",
     "client.MixinArmorFeatureRenderer",
+    "client.MixinBackgroundRenderer",
     "client.MixinCamera",
     "client.MixinClientWorld",
     "client.MixinEntityRenderDispatcher",