cn.academy.core.asm.APITransformerClient.java Source code

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Here is the source code for cn.academy.core.asm.APITransformerClient.java

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/**
 * Copyright (c) Lambda Innovation, 2013-2015
 * ??Lambda Innovation
 * http://www.lambdacraft.cn/
 *
 * AcademyCraft is open-source, and it is distributed under 
 * the terms of GNU General Public License. You can modify
 * and distribute freely as long as you follow the license.
 * AcademyCraft??GNU???
 * ????
 * http://www.gnu.org/licenses/gpl.html
 */
package cn.academy.core.asm;

import net.minecraft.launchwrapper.IClassTransformer;

import org.objectweb.asm.ClassReader;
import org.objectweb.asm.ClassVisitor;
import org.objectweb.asm.ClassWriter;
import org.objectweb.asm.MethodVisitor;
import org.objectweb.asm.Opcodes;

/**
 * Core asm transformer of ACAPI.
 * @author WeathFolD
 *
 */
public class APITransformerClient implements IClassTransformer {

    public APITransformerClient() {
    }

    @Override
    public byte[] transform(String n1, String n2, byte[] data) {

        if (n1.equals("net.minecraft.client.renderer.ItemRenderer")) {
            System.out.println("Transforming " + n1 + ", " + n2);
            ClassReader cr = new ClassReader(data);
            ClassWriter cw = new ClassWriter(Opcodes.ASM4);
            ClassVisitor cv = new ClassVisitor(Opcodes.ASM4, cw) {

                @Override
                public MethodVisitor visitMethod(int access, String name, String desc, String signature,
                        String[] exceptions) {
                    MethodVisitor mv = super.visitMethod(access, name, desc, signature, exceptions);
                    if (name.equals("renderItemInFirstPerson")) {
                        return new FPSkillEffect(mv);
                    } else if (name.equals("renderItem") && desc
                            .equals("(Lnet/minecraft/entity/EntityLivingBase;" + "Lnet/minecraft/item/ItemStack;"
                                    + "ILnet/minecraftforge/client/IItemRenderer$ItemRenderType;)V")) {
                        System.out.println("Injecting renderItem");
                        return new TPSkillEffect(mv);
                    }
                    return mv;
                }

            };

            cr.accept(cv, 0);
            return cw.toByteArray();
        }
        return data;
    }

    private static class TPSkillEffect extends MethodVisitor {

        int visTime = 0;

        public TPSkillEffect(MethodVisitor mv) {
            super(Opcodes.ASM4, mv);
        }

        @Override
        public void visitMethodInsn(int opcode, String owner, String name, String desc) {
            if (Opcodes.INVOKESTATIC == opcode && name.equals("glPopMatrix") && (++visTime == 4)) { //Before the last glPopMatrix() call
                System.out.println("Injected renderItem");
                mv.visitVarInsn(Opcodes.ALOAD, 1);
                mv.visitVarInsn(Opcodes.ALOAD, 2);
                mv.visitVarInsn(Opcodes.ALOAD, 4);
                mv.visitMethodInsn(Opcodes.INVOKESTATIC, "cn/academy/core/client/render/SkillRenderManager",
                        "renderThirdPerson",
                        "(Lnet/minecraft/entity/EntityLivingBase;" + "Lnet/minecraft/item/ItemStack;"
                                + "Lnet/minecraftforge/client/IItemRenderer$ItemRenderType;)V");
            }
            mv.visitMethodInsn(opcode, owner, name, desc);
        }
    }

    private static class FPSkillEffect extends MethodVisitor {

        int visTime = 0;

        public FPSkillEffect(MethodVisitor mv) {
            super(Opcodes.ASM4, mv);
        }

        @Override
        public void visitInsn(int opcode) {
            mv.visitInsn(opcode);
        }

        @Override
        public void visitMethodInsn(int opcode, String owner, String name, String desc) {
            if (Opcodes.INVOKESTATIC == opcode && name.equals("glDisable") && (++visTime == 2)) { //Before the glDisable(GL_RESCALE_NORMAL) call
                System.out.println("Injected renderInFirstPerson");
                mv.visitMethodInsn(Opcodes.INVOKESTATIC, "cn/academy/core/client/render/SkillRenderManager",
                        "renderFirstPerson", "()V");
            }
            mv.visitMethodInsn(opcode, owner, name, desc);
        }

        @Override
        public void visitFieldInsn(int opcode, String owner, String name, String desc) {
            mv.visitFieldInsn(opcode, owner, name, desc);
        }

    }

}