1 files changed, 129 insertions, 0 deletions
diff --git a/src/main/java/com/anthonyhilyard/iceberg/renderer/CustomItemRenderer.java b/src/main/java/com/anthonyhilyard/iceberg/renderer/CustomItemRenderer.java
new file mode 100644
index 0000000..29ce7d0
--- /dev/null
+++ b/src/main/java/com/anthonyhilyard/iceberg/renderer/CustomItemRenderer.java
@@ -0,0 +1,129 @@
+package com.anthonyhilyard.iceberg.renderer;
+
+import com.mojang.blaze3d.matrix.MatrixStack;
+import com.mojang.blaze3d.platform.GlStateManager.DestFactor;
+import com.mojang.blaze3d.platform.GlStateManager.SourceFactor;
+import com.mojang.blaze3d.systems.RenderSystem;
+
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+import org.lwjgl.opengl.GL11;
+
+import net.minecraft.client.Minecraft;
+import net.minecraft.client.gui.AbstractGui;
+import net.minecraft.client.renderer.IRenderTypeBuffer;
+import net.minecraft.client.renderer.ItemRenderer;
+import net.minecraft.client.renderer.RenderHelper;
+import net.minecraft.client.renderer.color.ItemColors;
+import net.minecraft.client.renderer.model.IBakedModel;
+import net.minecraft.client.renderer.model.ItemCameraTransforms;
+import net.minecraft.client.renderer.model.ModelManager;
+import net.minecraft.client.renderer.texture.AtlasTexture;
+import net.minecraft.client.renderer.texture.OverlayTexture;
+import net.minecraft.client.renderer.texture.TextureManager;
+import net.minecraft.client.shader.Framebuffer;
+import net.minecraft.item.ItemStack;
+
+/**
+ * An extended ItemRenderer that allows items to be rendered to framebuffer before drawing to screen.  
+ * This allows alpha values to be supported properly by all item types, even semi-transparent items.
+ */
+public class CustomItemRenderer extends ItemRenderer
+{
+	@SuppressWarnings("unused")
+	private static final Logger LOGGER = LogManager.getLogger();
+
+	private static Framebuffer iconFrameBuffer = null;
+	private Minecraft mc;
+	
+	public CustomItemRenderer(TextureManager textureManagerIn, ModelManager modelManagerIn, ItemColors itemColorsIn, Minecraft mcIn)
+	{
+		super(textureManagerIn, modelManagerIn, itemColorsIn);
+		mc = mcIn;
+
+		// Initialize the icon framebuffer if needed.
+		if (iconFrameBuffer == null)
+		{
+			// Use 96 x 96 pixels for the icon frame buffer so at 1.5 scale we get 4x resolution (for smooth icons on larger gui scales).
+			iconFrameBuffer = new Framebuffer(96, 96, true, Minecraft.ON_OSX);
+			iconFrameBuffer.setClearColor(0.0F, 0.0F, 0.0F, 0.0F);
+		}
+	}
+
+	@SuppressWarnings("deprecation")
+	public void renderItemModelIntoGUIWithAlpha(ItemStack stack, int x, int y, float alpha)
+	{
+		IBakedModel bakedModel = mc.getItemRenderer().getModel(stack, null, null);
+		Framebuffer lastFrameBuffer = mc.getMainRenderTarget();
+
+		// Bind the icon framebuffer so we can render to texture.
+		iconFrameBuffer.clear(Minecraft.ON_OSX);
+		iconFrameBuffer.bindWrite(true);
+		
+		RenderSystem.clear(GL11.GL_DEPTH_BUFFER_BIT, Minecraft.ON_OSX);
+		RenderSystem.matrixMode(GL11.GL_PROJECTION);
+		RenderSystem.pushMatrix();
+		RenderSystem.loadIdentity();
+		RenderSystem.ortho(0.0D, iconFrameBuffer.width, iconFrameBuffer.height, 0.0D, 1000.0D, 3000.0D);
+		RenderSystem.matrixMode(GL11.GL_MODELVIEW);
+		RenderSystem.pushMatrix();
+		RenderSystem.loadIdentity();
+		RenderSystem.translatef(0.0F, 0.0F, -2000.0F);
+		RenderHelper.setupFor3DItems();
+
+		mc.getTextureManager().bind(AtlasTexture.LOCATION_BLOCKS);
+		mc.getTextureManager().getTexture(AtlasTexture.LOCATION_BLOCKS).setFilter(false, false);
+		RenderSystem.enableRescaleNormal();
+		RenderSystem.enableAlphaTest();
+		RenderSystem.defaultAlphaFunc();
+		RenderSystem.enableBlend();
+		RenderSystem.blendFuncSeparate(SourceFactor.SRC_ALPHA, DestFactor.ONE_MINUS_SRC_ALPHA, SourceFactor.ONE, DestFactor.ONE_MINUS_SRC_ALPHA);
+		RenderSystem.color4f(1.0f, 1.0f, 1.0f, 1.0f);
+		RenderSystem.translatef(48.0f, 48.0f, 150.0f + this.blitOffset);
+		RenderSystem.scalef(1.0f, -1.0f, 1.0f);
+		RenderSystem.scalef(96.0f, 96.0f, 96.0f);
+		MatrixStack matrixStack = new MatrixStack();
+		IRenderTypeBuffer.Impl renderBuffer = Minecraft.getInstance().renderBuffers().bufferSource();
+		boolean isSideLit = !bakedModel.usesBlockLight();
+		if (isSideLit)
+		{
+			RenderHelper.setupForFlatItems();
+		}
+
+		render(stack, ItemCameraTransforms.TransformType.GUI, false, matrixStack, renderBuffer, 0xF000F0, OverlayTexture.NO_OVERLAY, bakedModel);
+		renderBuffer.endBatch();
+		RenderSystem.enableDepthTest();
+		if (isSideLit)
+		{
+			RenderHelper.setupFor3DItems();
+		}
+
+		RenderSystem.disableRescaleNormal();
+		RenderSystem.popMatrix();
+		RenderSystem.matrixMode(GL11.GL_PROJECTION);
+		RenderSystem.popMatrix();
+		RenderSystem.matrixMode(GL11.GL_MODELVIEW);
+
+		// Rebind the previous framebuffer, if there was one.
+		if (lastFrameBuffer != null)
+		{
+			lastFrameBuffer.bindWrite(true);
+
+			// Blit from the texture we just rendered to, respecting the alpha value given.
+			iconFrameBuffer.bindRead();
+			RenderSystem.enableAlphaTest();
+			RenderSystem.enableBlend();
+			RenderSystem.defaultBlendFunc();
+			RenderSystem.defaultAlphaFunc();
+			RenderSystem.disableCull();
+			RenderSystem.color4f(1.0f, 1.0f, 1.0f, alpha);
+			RenderSystem.scalef(1.0f, -1.0f, 1.0f);
+
+			AbstractGui.blit(new MatrixStack(), x, y - 18, 16, 16, 0, 0, iconFrameBuffer.width, iconFrameBuffer.height, iconFrameBuffer.width, iconFrameBuffer.height);
+		}
+		else
+		{
+			iconFrameBuffer.unbindWrite();
+		}
+	}
+}