Program: 22307
Project: 22307
Buggy source:
@Override public void renderTileEntityAt(TileEntityCrucible crucible,double x,double y,double z,float partialTicks,int destroyStage){
  IBlockState state=crucible.getWorld().getBlockState(crucible.getPos());
  EnumFacing facing=state.getValue(BlockCrucible.FACING);
  float angle=90F;
switch (facing) {
case WEST:
{
      angle=270F;
      break;
    }
case NORTH:
{
    angle=180F;
    break;
  }
case EAST:
{
  angle=90F;
  break;
}
case SOUTH:
{
angle=0F;
break;
}
default :
{
break;
}
}
GlStateManager.pushMatrix();
GlStateManager.enableRescaleNormal();
GlStateManager.color(1F,1F,1F,1F);
GlStateManager.translate(x,y,z);
int ticks=crucible.tipTicks;
Minecraft.getMinecraft().renderEngine.bindTexture(TextureMap.LOCATION_BLOCKS_TEXTURE);
GlStateManager.translate(0.5,0,0.5);
GlStateManager.rotate(angle,0F,1F,0F);
GlStateManager.scale(1F,-1F,-1F);
GlStateManager.translate(0,-0.5,0);
if (ticks > 135) {
ticks=(int)((ticks - 90) / 5.0F * 90);
GlStateManager.rotate((MathHelper.sin((float)(Math.PI * (ticks / 90.0F)))) * 5F,1F,0F,0F);
}
 else if (ticks > 120) {
ticks=(int)((ticks - 90) / 15.0F * 90);
GlStateManager.rotate((MathHelper.sin((float)(Math.PI * (ticks / 90.0F)))) * 15F,1F,0F,0F);
}
 else if (ticks > 90) {
ticks=(int)((ticks - 90) / 30.0F * 90);
GlStateManager.rotate((MathHelper.sin((float)(Math.PI * (ticks / 90.0F)))) * 30F,-1F,0F,0F);
}
 else {
GlStateManager.rotate((MathHelper.sin((float)(Math.PI * (ticks / 90.0F)))) * 75F,1F,0F,0F);
}
GlStateManager.translate(-0.5,0.5,-0.5);
GlStateManager.scale(1F,-1F,-1F);
IBakedModel model=Minecraft.getMinecraft().getBlockRendererDispatcher().getBlockModelShapes().getModelForState(state);
Minecraft.getMinecraft().getBlockRendererDispatcher().getBlockModelRenderer().renderModelBrightness(model,state,1F,false);
int fill=crucible.getFill();
if (fill > 0) {
GlStateManager.disableBlend();
float height=(2F + (fill / 90F) * 11F) / 16F;
GlStateManager.rotate(180F,1F,0F,0F);
GlStateManager.translate(0F,-height,-1F);
renderLiquid(crucible);
GlStateManager.enableBlend();
}
GlStateManager.popMatrix();
frame++;
if (frame == 20) {
frame=0;
}
}

Fixed version (ground truth):
@Override public void renderTileEntityAt(TileEntityCrucible crucible,double x,double y,double z,float partialTicks,int destroyStage){
  IBlockState state=crucible.getWorld().getBlockState(crucible.getPos());
  EnumFacing facing=state.getValue(BlockCrucible.FACING);
  float angle=90F;
switch (facing) {
case WEST:
{
      angle=270F;
      break;
    }
case NORTH:
{
    angle=180F;
    break;
  }
case EAST:
{
  angle=90F;
  break;
}
case SOUTH:
{
angle=0F;
break;
}
default :
{
break;
}
}
GlStateManager.pushMatrix();
GlStateManager.disableBlend();
GlStateManager.enableRescaleNormal();
GlStateManager.color(1F,1F,1F,1F);
GlStateManager.translate(x,y,z);
int ticks=crucible.tipTicks;
Minecraft.getMinecraft().renderEngine.bindTexture(TextureMap.LOCATION_BLOCKS_TEXTURE);
GlStateManager.translate(0.5,0,0.5);
GlStateManager.rotate(angle,0F,1F,0F);
GlStateManager.scale(1F,-1F,-1F);
GlStateManager.translate(0,-0.5,0);
if (ticks > 135) {
ticks=(int)((ticks - 90) / 5.0F * 90);
GlStateManager.rotate((MathHelper.sin((float)(Math.PI * (ticks / 90.0F)))) * 5F,1F,0F,0F);
}
 else if (ticks > 120) {
ticks=(int)((ticks - 90) / 15.0F * 90);
GlStateManager.rotate((MathHelper.sin((float)(Math.PI * (ticks / 90.0F)))) * 15F,1F,0F,0F);
}
 else if (ticks > 90) {
ticks=(int)((ticks - 90) / 30.0F * 90);
GlStateManager.rotate((MathHelper.sin((float)(Math.PI * (ticks / 90.0F)))) * 30F,-1F,0F,0F);
}
 else {
GlStateManager.rotate((MathHelper.sin((float)(Math.PI * (ticks / 90.0F)))) * 75F,1F,0F,0F);
}
GlStateManager.translate(-0.5,0.5,-0.5);
GlStateManager.scale(1F,-1F,-1F);
IBakedModel model=Minecraft.getMinecraft().getBlockRendererDispatcher().getBlockModelShapes().getModelForState(state);
Minecraft.getMinecraft().getBlockRendererDispatcher().getBlockModelRenderer().renderModelBrightness(model,state,1F,false);
int fill=crucible.getFill();
if (fill > 0) {
GlStateManager.disableBlend();
float height=(2F + (fill / 90F) * 11F) / 16F;
GlStateManager.rotate(180F,1F,0F,0F);
GlStateManager.translate(0F,-height,-1F);
renderLiquid(crucible);
GlStateManager.enableBlend();
}
GlStateManager.popMatrix();
frame++;
if (frame == 20) {
frame=0;
}
}