diff --git a/src/main/java/me/cortex/voxy/client/core/IrisVoxyRenderPipeline.java b/src/main/java/me/cortex/voxy/client/core/IrisVoxyRenderPipeline.java
index d23121d6..c1e461bc 100644
--- a/src/main/java/me/cortex/voxy/client/core/IrisVoxyRenderPipeline.java
+++ b/src/main/java/me/cortex/voxy/client/core/IrisVoxyRenderPipeline.java
@@ -109,6 +109,10 @@ public class IrisVoxyRenderPipeline extends AbstractRenderPipeline {
             glClear(GL_COLOR_BUFFER_BIT);
         }
 
+        if (this.data.useViewportDims) {
+            srcWidth = viewport.width;
+            srcHeight = viewport.height;
+        }
         this.initDepthStencil(sourceFramebuffer, this.fb.framebuffer.id, srcWidth, srcHeight, viewport.width, viewport.height);
         return this.fb.getDepthTex().id;
     }
diff --git a/src/main/java/me/cortex/voxy/client/iris/IrisShaderPatch.java b/src/main/java/me/cortex/voxy/client/iris/IrisShaderPatch.java
index a1c8e451..3bd97bd3 100644
--- a/src/main/java/me/cortex/voxy/client/iris/IrisShaderPatch.java
+++ b/src/main/java/me/cortex/voxy/client/iris/IrisShaderPatch.java
@@ -26,6 +26,7 @@ public class IrisShaderPatch {
     public static final boolean IMPERSONATE_DISTANT_HORIZONS = System.getProperty("voxy.impersonateDHShader", "false").equalsIgnoreCase("true");
 
 
+
     private static final class SSBODeserializer implements JsonDeserializer<Int2ObjectOpenHashMap<String>> {
         @Override
         public Int2ObjectOpenHashMap<String> deserialize(JsonElement json, Type typeOfT, JsonDeserializationContext context) throws JsonParseException {
@@ -157,6 +158,7 @@ public class IrisShaderPatch {
         public String taaOffset;
         public boolean excludeLodsFromVanillaDepth;
         public float[] renderScale;
+        public boolean useViewportDims;
         public boolean checkValid() {
             return this.opaqueDrawBuffers != null && this.translucentDrawBuffers != null && this.uniforms != null && this.opaquePatchData != null;
         }
@@ -178,6 +180,10 @@ public class IrisShaderPatch {
         }
     }
 
+    public boolean useViewportDims() {
+        return this.patchData.useViewportDims;
+    }
+
     public Int2ObjectMap<String> getSSBOs() {
         return new Int2ObjectLinkedOpenHashMap<>(this.ssbos);
     }
diff --git a/src/main/java/me/cortex/voxy/client/iris/IrisVoxyRenderPipelineData.java b/src/main/java/me/cortex/voxy/client/iris/IrisVoxyRenderPipelineData.java
index 50435f0d..0e5e59a3 100644
--- a/src/main/java/me/cortex/voxy/client/iris/IrisVoxyRenderPipelineData.java
+++ b/src/main/java/me/cortex/voxy/client/iris/IrisVoxyRenderPipelineData.java
@@ -49,6 +49,8 @@ public class IrisVoxyRenderPipelineData {
     public final boolean renderToVanillaDepth;
     public final float[] resolutionScale;
     public final String TAA;
+    public final boolean useViewportDims;
+
     private IrisVoxyRenderPipelineData(IrisShaderPatch patch, int[] opaqueDrawTargets, int[] translucentDrawTargets, StructLayout uniformSet, Runnable blendingSetup, ImageSet imageSet, SSBOSet ssboSet) {
         this.opaqueDrawTargets = opaqueDrawTargets;
         this.translucentDrawTargets = translucentDrawTargets;
@@ -61,6 +63,7 @@ public class IrisVoxyRenderPipelineData {
         this.renderToVanillaDepth = patch.emitToVanillaDepth();
         this.TAA = patch.getTAAShift();
         this.resolutionScale = patch.getRenderScale();
+        this.useViewportDims = patch.useViewportDims();
     }
 
     public SSBOSet getSsboSet() {