Add compatibility for GLSL Shaders

src/main/java/com/replaymod/compat/shaders/mixin/MixinShaderEntityRenderer.java

@@ -0,0 +1,52 @@
+package com.replaymod.compat.shaders.mixin;
+
+import com.replaymod.replay.ReplayHandler;
+import com.replaymod.replay.ReplayModReplay;
+import net.minecraft.client.Minecraft;
+import net.minecraft.client.renderer.EntityRenderer;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Shadow;
+import org.spongepowered.asm.mixin.injection.At;
+import org.spongepowered.asm.mixin.injection.Inject;
+import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+
+import java.lang.reflect.Field;
+
+@Mixin(EntityRenderer.class)
+public abstract class MixinShaderEntityRenderer {
+
+    @Shadow
+    public Minecraft mc;
+
+    private static Field replayModCompat_frameTimeCounterField = null;
+
+    static {
+        replayModCompat_initFrameTimeCounterField();
+    }
+
+    private static void replayModCompat_initFrameTimeCounterField() {
+        try {
+            replayModCompat_frameTimeCounterField = Class.forName("shadersmod.client.Shaders")
+                    .getDeclaredField("frameTimeCounter");
+            replayModCompat_frameTimeCounterField.setAccessible(true);
+        } catch (ClassNotFoundException ignore) {
+            // no shaders mod installed
+        } catch (NoSuchFieldException e) {
+            // the field wasn't found. Has it been renamed?
+            e.printStackTrace();
+        }
+    }
+
+    @Inject(method = "renderWorld", at = @At(value = "INVOKE", target = "Lnet/minecraft/client/renderer/GlStateManager;enableDepth()V"))
+    private void replayModCompat_updateShaderFrameTimeCounter(CallbackInfo ignore) {
+        if (replayModCompat_frameTimeCounterField != null) {
+            ReplayHandler replayHandler = ReplayModReplay.instance.getReplayHandler();
+            float timestamp = replayHandler.getReplaySender().currentTimeStamp() / 1000f % 3600f;
+            try {
+                replayModCompat_frameTimeCounterField.set(null, timestamp);
+            } catch (Exception e) {
+                e.printStackTrace();
+            }
+        }
+    }
+}