Implement ODS rendering via Iris Shader for MC 1.17

src/main/resources/assets/replaymod/iris/ods/shaders/gbuffers_textured_lit.fsh

@@ -0,0 +1,15 @@
+#version 120
+
+uniform sampler2D texture;
+uniform sampler2D lightmap;
+
+varying vec4 color;
+varying vec2 texcoord;
+varying vec2 lmcoord;
+
+void main() {
+    vec4 lightmap = texture2D(lightmap, lmcoord);
+    vec4 color = texture2D(texture, texcoord) * color;
+    color *= lightmap;
+    gl_FragColor = color;
+}

src/main/resources/assets/replaymod/iris/ods/shaders/gbuffers_textured_lit.vsh

@@ -0,0 +1,69 @@
+#version 120
+
+varying vec4 color;
+varying vec2 texcoord;
+varying vec2 lmcoord;
+
+uniform int leftEye;
+uniform int direction;
+
+const float eyeDistance = 0.14;
+
+void main() {
+    // Transform to view space
+    vec4 position = gl_ModelViewMatrix * gl_Vertex;
+
+    // Distort for ODS
+    //  O := The origin
+    //  P := The current vertex/point
+    //  T := Point of tangency with the tangent going through P
+    // Distance between P and O
+    float distPO = sqrt(position.x * position.x + position.z * position.z);
+    float distTO = eyeDistance * 0.5;
+    // Angle between PO and PT
+    float angP = acos(distTO / distPO);
+    // Angle between PO and TO (angle at the origin)
+    float angO = 90.0 - angP;
+    if (leftEye == 0) {
+        angO = -angO;
+    }
+    // The angel of OP within the circle, that is between OP and O(0,1)
+    float angOP = atan(position.x, position.z);
+    // The angle of OT within the circle, that is between OT and O(0,1)
+    float angOT = angO + angOP;
+    // Calculate the vector between O and T and finally move the vertex by that vector
+    position -= vec4(distTO * sin(angOT), 0, distTO * cos(angOT), 0);
+
+    // Rotate for different cubic views
+    float z;
+    if (direction == 0) { // LEFT
+        z = position.z;
+        position.z = position.x;
+        position.x = -z;
+    } else if (direction == 1) { // RIGHT
+        z = position.z;
+        position.z = -position.x;
+        position.x = z;
+    } else if (direction == 2) { // FRONT
+        // No changes required
+    } else if (direction == 3) { // BACK
+        position.x = -position.x;
+        position.z = -position.z;
+    } else if (direction == 4) { // TOP
+        z = position.z;
+        position.z = -position.y;
+        position.y = z;
+    } else if (direction == 5) { // BOTTOM
+        z = position.z;
+        position.z = position.y;
+        position.y = -z;
+    }
+
+    // Transform to screen space
+    gl_Position = gl_ProjectionMatrix * position;
+
+    // Misc.
+    color = gl_Color;
+    texcoord = (gl_TextureMatrix[0] * gl_MultiTexCoord0).xy;
+    lmcoord = (gl_TextureMatrix[1] * gl_MultiTexCoord1).xy;
+}

src/main/resources/mixins.render.replaymod.json

@@ -20,6 +20,10 @@
     "Mixin_StabilizeCamera",
     "Mixin_Stereoscopic_Camera",
     "Mixin_Stereoscopic_HandRenderPass",
+    //#if MC>=11600
+    "Mixin_AddIrisOdsShaderUniforms",
+    "Mixin_LoadIrisOdsShaderPack",
+    //#endif
     //#if MC>=10800
     //#if MC>=11500
     "Mixin_BlockOnChunkRebuilds",