CC-Tweaked/src/main/java/dan200/computercraft/client/render/ItemMapLikeRenderer.java

/*
 * This file is part of ComputerCraft - http://www.computercraft.info
 * Copyright Daniel Ratcliffe, 2011-2022. Do not distribute without permission.
 * Send enquiries to dratcliffe@gmail.com
 */
package dan200.computercraft.client.render;

import com.mojang.blaze3d.vertex.PoseStack;
import com.mojang.math.Vector3f;
import net.minecraft.client.Minecraft;
import net.minecraft.client.renderer.ItemInHandRenderer;
import net.minecraft.client.renderer.MultiBufferSource;
import net.minecraft.client.renderer.block.model.ItemTransforms;
import net.minecraft.util.Mth;
import net.minecraft.world.InteractionHand;
import net.minecraft.world.entity.HumanoidArm;
import net.minecraft.world.entity.LivingEntity;
import net.minecraft.world.entity.player.Player;
import net.minecraft.world.item.ItemStack;

public abstract class ItemMapLikeRenderer
{
    /**
     * The main rendering method for the item.
     *
     * @param transform The matrix transformation stack
     * @param render    The buffer to render to
     * @param stack     The stack to render
     * @param light     The packed lightmap coordinates.
     * @see ItemInHandRenderer#renderItem(LivingEntity, ItemStack, ItemTransforms.TransformType, boolean, PoseStack, MultiBufferSource, int)
     */
    protected abstract void renderItem( PoseStack transform, MultiBufferSource render, ItemStack stack, int light );

    protected void renderItemFirstPerson( PoseStack transform, MultiBufferSource render, int lightTexture, InteractionHand hand, float pitch, float equipProgress, float swingProgress, ItemStack stack )
    {
        Player player = Minecraft.getInstance().player;

        transform.pushPose();
        if( hand == InteractionHand.MAIN_HAND && player.getOffhandItem().isEmpty() )
        {
            renderItemFirstPersonCenter( transform, render, lightTexture, pitch, equipProgress, swingProgress, stack );
        }
        else
        {
            renderItemFirstPersonSide(
                transform, render, lightTexture,
                hand == InteractionHand.MAIN_HAND ? player.getMainArm() : player.getMainArm().getOpposite(),
                equipProgress, swingProgress, stack
            );
        }
        transform.popPose();
    }

    /**
     * Renders the item to one side of the player.
     *
     * @param transform     The matrix transformation stack
     * @param render        The buffer to render to
     * @param combinedLight The current light level
     * @param side          The side to render on
     * @param equipProgress The equip progress of this item
     * @param swingProgress The swing progress of this item
     * @param stack         The stack to render
     * @see ItemInHandRenderer#renderOneHandedMap(PoseStack, MultiBufferSource, int, float, HumanoidArm, float, ItemStack)
     */
    private void renderItemFirstPersonSide( PoseStack transform, MultiBufferSource render, int combinedLight, HumanoidArm side, float equipProgress, float swingProgress, ItemStack stack )
    {
        Minecraft minecraft = Minecraft.getInstance();
        float offset = side == HumanoidArm.RIGHT ? 1f : -1f;
        transform.translate( offset * 0.125f, -0.125f, 0f );

        // If the player is not invisible then render a single arm
        if( !minecraft.player.isInvisible() )
        {
            transform.pushPose();
            transform.mulPose( Vector3f.ZP.rotationDegrees( offset * 10f ) );
            minecraft.getEntityRenderDispatcher().getItemInHandRenderer().renderPlayerArm( transform, render, combinedLight, equipProgress, swingProgress, side );
            transform.popPose();
        }

        // Setup the appropriate transformations. This is just copied from the
        // corresponding method in ItemRenderer.
        transform.pushPose();
        transform.translate( offset * 0.51f, -0.08f + equipProgress * -1.2f, -0.75f );
        float f1 = Mth.sqrt( swingProgress );
        float f2 = Mth.sin( f1 * (float) Math.PI );
        float f3 = -0.5f * f2;
        float f4 = 0.4f * Mth.sin( f1 * ((float) Math.PI * 2f) );
        float f5 = -0.3f * Mth.sin( swingProgress * (float) Math.PI );
        transform.translate( offset * f3, f4 - 0.3f * f2, f5 );
        transform.mulPose( Vector3f.XP.rotationDegrees( f2 * -45f ) );
        transform.mulPose( Vector3f.YP.rotationDegrees( offset * f2 * -30f ) );

        renderItem( transform, render, stack, combinedLight );

        transform.popPose();
    }

    /**
     * Render an item in the middle of the screen.
     *
     * @param transform     The matrix transformation stack
     * @param render        The buffer to render to
     * @param combinedLight The current light level
     * @param pitch         The pitch of the player
     * @param equipProgress The equip progress of this item
     * @param swingProgress The swing progress of this item
     * @param stack         The stack to render
     * @see ItemInHandRenderer#renderTwoHandedMap(PoseStack, MultiBufferSource, int, float, float, float)
     */
    private void renderItemFirstPersonCenter( PoseStack transform, MultiBufferSource render, int combinedLight, float pitch, float equipProgress, float swingProgress, ItemStack stack )
    {
        Minecraft minecraft = Minecraft.getInstance();
        ItemInHandRenderer renderer = minecraft.getEntityRenderDispatcher().getItemInHandRenderer();

        // Setup the appropriate transformations. This is just copied from the
        // corresponding method in ItemRenderer.
        float swingRt = Mth.sqrt( swingProgress );
        float tX = -0.2f * Mth.sin( swingProgress * (float) Math.PI );
        float tZ = -0.4f * Mth.sin( swingRt * (float) Math.PI );
        transform.translate( 0, -tX / 2, tZ );

        float pitchAngle = renderer.calculateMapTilt( pitch );
        transform.translate( 0, 0.04F + equipProgress * -1.2f + pitchAngle * -0.5f, -0.72f );
        transform.mulPose( Vector3f.XP.rotationDegrees( pitchAngle * -85.0f ) );
        if( !minecraft.player.isInvisible() )
        {
            transform.pushPose();
            transform.mulPose( Vector3f.YP.rotationDegrees( 90.0F ) );
            renderer.renderMapHand( transform, render, combinedLight, HumanoidArm.RIGHT );
            renderer.renderMapHand( transform, render, combinedLight, HumanoidArm.LEFT );
            transform.popPose();
        }

        float rX = Mth.sin( swingRt * (float) Math.PI );
        transform.mulPose( Vector3f.XP.rotationDegrees( rX * 20.0F ) );
        transform.scale( 2.0F, 2.0F, 2.0F );

        renderItem( transform, render, stack, combinedLight );
    }
}