Begin work on framebuffer renderer

src/main/java/com/fusionflux/portalcubed/client/render/portal/FramebufferRenderer.java

@@ -0,0 +1,71 @@
+package com.fusionflux.portalcubed.client.render.portal;
+
+import com.fusionflux.portalcubed.entity.ExperimentalPortal;
+import com.fusionflux.portalcubed.mixin.client.MinecraftAccessor;
+import com.mojang.blaze3d.pipeline.RenderTarget;
+import com.mojang.blaze3d.pipeline.TextureTarget;
+import com.mojang.blaze3d.platform.GlStateManager;
+import com.mojang.blaze3d.vertex.PoseStack;
+import net.minecraft.client.Minecraft;
+
+import java.util.ArrayDeque;
+import java.util.Queue;
+
+import static com.mojang.blaze3d.platform.GlConst.GL_COLOR_BUFFER_BIT;
+import static com.mojang.blaze3d.platform.GlConst.GL_DEPTH_BUFFER_BIT;
+
+public class FramebufferRenderer extends PortalRenderer {
+    // Nice setup, fastutil (IntArrayFIFOQueue isn't a priority queue)
+    private static final Queue<RenderTarget> FREE_TARGETS = new ArrayDeque<>();
+
+    private int portalLayer = 0;
+
+    private static RenderTarget getRenderTarget(int width, int height) {
+        final RenderTarget target = FREE_TARGETS.poll();
+        if (target == null) {
+            return new TextureTarget(width, height, true, Minecraft.ON_OSX);
+        }
+        if (target.width != width || target.height != height) {
+            target.resize(width, height, Minecraft.ON_OSX);
+        }
+        return target;
+    }
+
+    private static void freeRenderTarget(RenderTarget target) {
+        if (!FREE_TARGETS.offer(target)) {
+            target.destroyBuffers();
+        }
+    }
+
+    @Override
+    public boolean enabled(ExperimentalPortal portal) {
+        return portalLayer < MAX_PORTAL_LAYER && portal.getActive();
+    }
+
+    @Override
+    public void preRender(ExperimentalPortal portal, float tickDelta, PoseStack poseStack) {
+    }
+
+    @Override
+    public void postRender(ExperimentalPortal portal, float tickDelta, PoseStack poseStack) {
+        final Minecraft minecraft = Minecraft.getInstance();
+        final RenderTarget oldTarget = minecraft.getMainRenderTarget();
+        final RenderTarget newTarget = getRenderTarget(oldTarget.width, oldTarget.height);
+
+        ((MinecraftAccessor)minecraft).setMainRenderTarget(newTarget);
+        newTarget.bindWrite(true);
+
+        GlStateManager._clearColor(1, 0, 1, 1);
+        GlStateManager._clearDepth(1);
+        GlStateManager._clear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT, Minecraft.ON_OSX);
+
+        portalLayer++;
+        renderWorld(portal, tickDelta, poseStack);
+        portalLayer--;
+
+        ((MinecraftAccessor)minecraft).setMainRenderTarget(oldTarget);
+        oldTarget.bindWrite(true);
+
+        freeRenderTarget(newTarget);
+    }
+}

src/main/java/com/fusionflux/portalcubed/client/render/portal/PortalRenderers.java

@@ -5,7 +5,7 @@
 public enum PortalRenderers {
     DISABLED(DisabledRenderer::new),
     STENCIL(StencilRenderer::new),
-    FRAMEBUFFER(DisabledRenderer::new);
+    FRAMEBUFFER(FramebufferRenderer::new);
 
     public final Supplier<? extends PortalRenderer> creator;
 

src/main/java/com/fusionflux/portalcubed/mixin/client/MinecraftAccessor.java

@@ -0,0 +1,14 @@
+package com.fusionflux.portalcubed.mixin.client;
+
+import com.mojang.blaze3d.pipeline.RenderTarget;
+import net.minecraft.client.Minecraft;
+import org.spongepowered.asm.mixin.Mixin;
+import org.spongepowered.asm.mixin.Mutable;
+import org.spongepowered.asm.mixin.gen.Accessor;
+
+@Mixin(Minecraft.class)
+public interface MinecraftAccessor {
+    @Mutable
+    @Accessor("mainRenderTarget")
+    void setMainRenderTarget(RenderTarget target);
+}

src/main/resources/assets/portalcubed/lang/en_us.json

@@ -327,10 +327,10 @@
   "portalcubed.midnightconfig.enum.TitleScreenMode.P1": "Portal 1",
   "portalcubed.midnightconfig.enum.TitleScreenMode.P2": "Portal 2",
   "portalcubed.midnightconfig.staticPortalItemDrops": "Static Portal Item Drops",
-  "portalcubed.midnightconfig.renderer": "Portal Renderer",
+  "portalcubed.midnightconfig.renderer": "Portal Renderer (in development)",
   "portalcubed.midnightconfig.enum.PortalRenderers.DISABLED": "Disabled",
-  "portalcubed.midnightconfig.enum.PortalRenderers.STENCIL": "Stencil \u00a7c(BROKEN)\u00a7r",
-  "portalcubed.midnightconfig.enum.PortalRenderers.FRAMEBUFFER": "Framebuffer \u00a7c(NOT IMPLEMENTED)\u00a7r",
+  "portalcubed.midnightconfig.enum.PortalRenderers.STENCIL": "Stencil",
+  "portalcubed.midnightconfig.enum.PortalRenderers.FRAMEBUFFER": "Framebuffer",
 
   "death.attack.portalcubed.acid": "%s was dissolved in toxic goo",
   "death.attack.portalcubed.fizzle": "%s got fizzled",

src/main/resources/portalcubed.mixins.json

@@ -34,6 +34,7 @@
     "client.KeyboardInputMixin",
     "client.KeyMappingAccessor",
     "client.LocalPlayerMixin",
+    "client.MinecraftAccessor",
     "client.MinecraftMixin",
     "client.ModelBakeryMixin",
     "client.MouseHandlerMixin",