001    package net.minecraft.src;
002    
003    import cpw.mods.fml.common.Side;
004    import cpw.mods.fml.common.asm.SideOnly;
005    import java.nio.FloatBuffer;
006    import org.lwjgl.opengl.GL11;
007    
008    @SideOnly(Side.CLIENT)
009    public class RenderHelper
010    {
011        /** Float buffer used to set OpenGL material colors */
012        private static FloatBuffer colorBuffer = GLAllocation.createDirectFloatBuffer(16);
013        private static final Vec3 field_82884_b = Vec3.createVectorHelper(0.20000000298023224D, 1.0D, -0.699999988079071D).normalize();
014        private static final Vec3 field_82885_c = Vec3.createVectorHelper(-0.20000000298023224D, 1.0D, 0.699999988079071D).normalize();
015    
016        /**
017         * Disables the OpenGL lighting properties enabled by enableStandardItemLighting
018         */
019        public static void disableStandardItemLighting()
020        {
021            GL11.glDisable(GL11.GL_LIGHTING);
022            GL11.glDisable(GL11.GL_LIGHT0);
023            GL11.glDisable(GL11.GL_LIGHT1);
024            GL11.glDisable(GL11.GL_COLOR_MATERIAL);
025        }
026    
027        /**
028         * Sets the OpenGL lighting properties to the values used when rendering blocks as items
029         */
030        public static void enableStandardItemLighting()
031        {
032            GL11.glEnable(GL11.GL_LIGHTING);
033            GL11.glEnable(GL11.GL_LIGHT0);
034            GL11.glEnable(GL11.GL_LIGHT1);
035            GL11.glEnable(GL11.GL_COLOR_MATERIAL);
036            GL11.glColorMaterial(GL11.GL_FRONT_AND_BACK, GL11.GL_AMBIENT_AND_DIFFUSE);
037            float var0 = 0.4F;
038            float var1 = 0.6F;
039            float var2 = 0.0F;
040            GL11.glLight(GL11.GL_LIGHT0, GL11.GL_POSITION, setColorBuffer(field_82884_b.xCoord, field_82884_b.yCoord, field_82884_b.zCoord, 0.0D));
041            GL11.glLight(GL11.GL_LIGHT0, GL11.GL_DIFFUSE, setColorBuffer(var1, var1, var1, 1.0F));
042            GL11.glLight(GL11.GL_LIGHT0, GL11.GL_AMBIENT, setColorBuffer(0.0F, 0.0F, 0.0F, 1.0F));
043            GL11.glLight(GL11.GL_LIGHT0, GL11.GL_SPECULAR, setColorBuffer(var2, var2, var2, 1.0F));
044            GL11.glLight(GL11.GL_LIGHT1, GL11.GL_POSITION, setColorBuffer(field_82885_c.xCoord, field_82885_c.yCoord, field_82885_c.zCoord, 0.0D));
045            GL11.glLight(GL11.GL_LIGHT1, GL11.GL_DIFFUSE, setColorBuffer(var1, var1, var1, 1.0F));
046            GL11.glLight(GL11.GL_LIGHT1, GL11.GL_AMBIENT, setColorBuffer(0.0F, 0.0F, 0.0F, 1.0F));
047            GL11.glLight(GL11.GL_LIGHT1, GL11.GL_SPECULAR, setColorBuffer(var2, var2, var2, 1.0F));
048            GL11.glShadeModel(GL11.GL_FLAT);
049            GL11.glLightModel(GL11.GL_LIGHT_MODEL_AMBIENT, setColorBuffer(var0, var0, var0, 1.0F));
050        }
051    
052        /**
053         * Update and return colorBuffer with the RGBA values passed as arguments
054         */
055        private static FloatBuffer setColorBuffer(double par0, double par2, double par4, double par6)
056        {
057            return setColorBuffer((float)par0, (float)par2, (float)par4, (float)par6);
058        }
059    
060        /**
061         * Update and return colorBuffer with the RGBA values passed as arguments
062         */
063        private static FloatBuffer setColorBuffer(float par0, float par1, float par2, float par3)
064        {
065            colorBuffer.clear();
066            colorBuffer.put(par0).put(par1).put(par2).put(par3);
067            colorBuffer.flip();
068            return colorBuffer;
069        }
070    
071        /**
072         * Sets OpenGL lighting for rendering blocks as items inside GUI screens (such as containers).
073         */
074        public static void enableGUIStandardItemLighting()
075        {
076            GL11.glPushMatrix();
077            GL11.glRotatef(-30.0F, 0.0F, 1.0F, 0.0F);
078            GL11.glRotatef(165.0F, 1.0F, 0.0F, 0.0F);
079            enableStandardItemLighting();
080            GL11.glPopMatrix();
081        }
082    }