@@ -294,18 +294,39 @@
        // Only the controller runs the terminal tick
        if (be.terminal == null || !be.terminalStarted) return;
        long t0 = System.nanoTime();
        boolean alive = be.terminal.pollPty();
        long t1 = System.nanoTime();
        if (!alive) {
            be.stopTerminal();
            return;
        }
        boolean dirty = false;
        if (be.pixelBuffer != null) {
            be.pixelBuffer.rewind();
            dirty = be.terminal.getPixelData(be.pixelBuffer);
            boolean dirty = be.terminal.getPixelData(be.pixelBuffer);
            if (dirty) {
                be.textureNeedsUpdate = true;
            }
        }
        long t2 = System.nanoTime();
        // Profiling: print every 100 ticks
        be.tickPollNs += (t1 - t0);
        be.tickRenderNs += (t2 - t1);
        be.tickCount++;
        if (be.tickCount % 100 == 0) {
            System.out.printf("[AlacrittyMC-Perf] Tick avg: pollPty=%.2fms getPixelData=%.2fms (dirty=%b, %dx%d)%n",
                    (be.tickPollNs / 1e6) / 100, (be.tickRenderNs / 1e6) / 100,
                    dirty, be.pixelWidth, be.pixelHeight);
            be.tickPollNs = 0;
            be.tickRenderNs = 0;
        }
    }
    // Profiling accumulators
    private long tickPollNs = 0, tickRenderNs = 0;
    private int tickCount = 0;
    // ==================== ACCESSORS ====================

@@ -35,5 +35,15 @@
    private long lastFrameTime = 0;
    private final Set<Long> uploadedThisFrame = new HashSet<>();
    // Profiling: accumulate timings and print every 100 frames
    private long profileFrameCount = 0;
    private long profileUploadNs = 0;
    private long profileRenderNs = 0;
    private long profileRainNs = 0;
    private int profileUploadCount = 0;
    private int profileRenderCount = 0;
    private int profileRainCount = 0;
    private int profileUploadPixels = 0;
    public TerminalBlockRenderer(BlockEntityRendererProvider.Context context) {
    }
@@ -80,7 +90,11 @@
            if (!uploadedThisFrame.contains(texKey)) {
                ByteBuffer buf = dataSource.getPixelBuffer();
                if (buf != null) {
                    long t0 = System.nanoTime();
                    termTex.upload(buf, dataSource.getPixelWidth(), dataSource.getPixelHeight());
                    profileUploadNs += System.nanoTime() - t0;
                    profileUploadCount++;
                    profileUploadPixels += dataSource.getPixelWidth() * dataSource.getPixelHeight();
                    dataSource.clearTextureUpdateFlag();
                }
                uploadedThisFrame.add(texKey);
@@ -127,6 +141,17 @@
        }
        poseStack.popPose();
        profileRenderCount++;
        if (profileRenderCount % 500 == 0) {
            System.out.printf("[AlacrittyMC-Perf] Last 500 renders: uploads=%d (%.2fms avg, %dpx avg) totalRenders=%d%n",
                    profileUploadCount,
                    profileUploadCount > 0 ? (profileUploadNs / 1e6) / profileUploadCount : 0,
                    profileUploadCount > 0 ? profileUploadPixels / profileUploadCount : 0,
                    profileRenderCount);
            profileUploadNs = 0; profileUploadCount = 0; profileUploadPixels = 0;
            profileRenderCount = 0;
        }
    }
    private void applyFacingRotation(PoseStack poseStack, Direction facing) {

@@ -1,6 +1,7 @@
package io.fangorn.alacrittymc.client.renderer;
import com.mojang.blaze3d.platform.NativeImage;
import io.fangorn.alacrittymc.mixin.NativeImageAccessor;
import net.minecraft.client.Minecraft;
import net.minecraft.client.renderer.RenderType;
import net.minecraft.client.renderer.texture.DynamicTexture;
@@ -11,6 +12,8 @@
/**
 * Wraps a DynamicTexture that displays terminal pixel data.
 * Uses bulk memcpy for upload — the Rust renderer outputs ABGR matching
 * NativeImage's internal format, so we copy directly to the backing memory.
 */
public class TerminalTexture implements AutoCloseable {
    private final DynamicTexture texture;
@@ -18,6 +21,7 @@
    private final ResourceLocation textureId;
    private final int width;
    private final int height;
    private final long nativePixelPtr; // Cached pointer to NativeImage's backing memory
    public TerminalTexture(int width, int height) {
        this.width = width;
@@ -26,54 +30,40 @@
        this.texture = new DynamicTexture(image);
        this.textureId = Minecraft.getInstance().getTextureManager()
                .register("alacrittymc_terminal", texture);
        // Cache the native pointer (stable for the lifetime of the NativeImage)
        this.nativePixelPtr = ((NativeImageAccessor) (Object) image).getPixels();
    }
    /**
     * Upload pixel data from a ByteBuffer to the GPU texture.
     *
     * The Rust renderer outputs pixels in ABGR byte order, which matches
     * NativeImage's internal format exactly. This allows a bulk memcpy
     * Upload pixel data from a direct ByteBuffer to the GPU texture.
     * Uses a single memcpy (Rust ABGR → NativeImage ABGR) instead of per-pixel loop.
     * instead of per-pixel conversion (~345K pixels → single copy).
     */
    public void upload(ByteBuffer pixelData, int w, int h) {
        if (w != width || h != height) return;
        int size = w * h * 4;
        pixelData.rewind();
        // Bulk copy: Rust ABGR output matches NativeImage ABGR format
        // NativeImage stores pixel data in native memory accessible via its pixels pointer
        if (nativePixelPtr != 0 && pixelData.isDirect()) {
            // Fast path: bulk copy from direct ByteBuffer to NativeImage's native memory
        // We write directly via setPixelRGBA which despite the name takes ABGR-packed ints
        // For maximum performance, copy 4 bytes at a time as ints
        for (int i = 0; i < w * h; i++) {
            int abgr = pixelData.getInt();
            image.setPixelRGBA(i % w, i / w, abgr);
            long srcAddr = MemoryUtil.memAddress(pixelData);
            MemoryUtil.memCopy(srcAddr, nativePixelPtr, size);
        } else {
            // Fallback: per-pixel copy (non-direct buffer or missing pointer)
            for (int i = 0; i < w * h; i++) {
                image.setPixelRGBA(i % w, i / w, pixelData.getInt());
            }
        }
        texture.upload();
    }
    /**
     * Get a RenderType suitable for rendering this texture on a block face.
     * Uses textIntensity() which has no backface culling, ensuring the quad
     * is visible regardless of camera direction.
     */
    public RenderType getRenderType() {
        // Use text() — same render type as MC's MapRenderer
        // Vertex format: POSITION_COLOR_TEX_LIGHTMAP (vertex, color, uv, uv2)
        return RenderType.text(textureId);
    }
    /**
     * Get a RenderType that renders with "see-through" (no depth test),
     * useful for rendering the terminal through other transparent blocks.
     */
    public RenderType getRenderTypeSeeThrough() {
        return RenderType.textSeeThrough(textureId);
    }
    public ResourceLocation getTextureId() {
        return textureId;
    }
    public ResourceLocation getTextureId() { return textureId; }
    public int getWidth() { return width; }
    public int getHeight() { return height; }

@@ -1,0 +1,15 @@
package io.fangorn.alacrittymc.mixin;
import com.mojang.blaze3d.platform.NativeImage;
import org.spongepowered.asm.mixin.Mixin;
import org.spongepowered.asm.mixin.gen.Accessor;
/**
 * Mixin accessor to get the raw pixel pointer from NativeImage.
 * Needed for bulk memcpy upload (bypassing per-pixel setPixelRGBA).
 */
@Mixin(NativeImage.class)
public interface NativeImageAccessor {
    @Accessor("pixels")
    long getPixels();
}

@@ -3,7 +3,8 @@
  "package": "io.fangorn.alacrittymc.mixin",
  "compatibilityLevel": "JAVA_17",
  "client": [
    "KeyboardHandlerMixin"
    "KeyboardHandlerMixin",
    "NativeImageAccessor"
  ],
  "injectors": {
    "defaultRequire": 1

@@ -23,9 +23,9 @@
    // Single block test
    private static BlockPos singlePos = null;
    // Multi-block test (3x2 grid)
    // Multi-block test (4x3 grid for perf testing)
    private static BlockPos multiOrigin = null;
    private static final int MULTI_W = 3, MULTI_H = 2;
    private static final int MULTI_W = 4, MULTI_H = 3;
    private static int testsPassed = 0;
    private static int testsFailed = 0;
@@ -191,7 +191,8 @@
            }
        }
        if (tickCounter >= 80) { phase = 6; tickCounter = 0; }
        // Wait longer for perf data collection (200 ticks = 10 seconds)
        if (tickCounter >= 200) { phase = 6; tickCounter = 0; }
    }
    private static void screenshotAndAnalyze(Minecraft mc) {