/**
* Copyright (c) 2008-2012 Ardor Labs, Inc.
*
* This file is part of Ardor3D.
*
* Ardor3D is free software: you can redistribute it and/or modify it
* under the terms of its license which may be found in the accompanying
* LICENSE file or at <http://www.ardor3d.com/LICENSE>.
*/
package com.ardor3d.scene.state.lwjgl;
import org.lwjgl.opengl.EXTStencilTwoSide;
import org.lwjgl.opengl.EXTStencilWrap;
import org.lwjgl.opengl.GL11;
import com.ardor3d.renderer.ContextCapabilities;
import com.ardor3d.renderer.ContextManager;
import com.ardor3d.renderer.RenderContext;
import com.ardor3d.renderer.state.RenderState.StateType;
import com.ardor3d.renderer.state.StencilState;
import com.ardor3d.renderer.state.StencilState.StencilFunction;
import com.ardor3d.renderer.state.StencilState.StencilOperation;
import com.ardor3d.renderer.state.record.StencilStateRecord;
public abstract class LwjglStencilStateUtil {
public static void apply(final StencilState state) {
// ask for the current state record
final RenderContext context = ContextManager.getCurrentContext();
final ContextCapabilities caps = context.getCapabilities();
final StencilStateRecord record = (StencilStateRecord) context.getStateRecord(StateType.Stencil);
context.setCurrentState(StateType.Stencil, state);
setEnabled(state.isEnabled(), caps.isTwoSidedStencilSupported() ? state.isUseTwoSided() : false, record, caps);
if (state.isEnabled()) {
if (state.isUseTwoSided() && caps.isTwoSidedStencilSupported()) {
EXTStencilTwoSide.glActiveStencilFaceEXT(GL11.GL_BACK);
applyMask(state.getStencilWriteMaskBack(), record, 2);
applyFunc(getGLStencilFunction(state.getStencilFunctionBack()), state.getStencilReferenceBack(),
state.getStencilFuncMaskBack(), record, 2);
applyOp(getGLStencilOp(state.getStencilOpFailBack(), caps),
getGLStencilOp(state.getStencilOpZFailBack(), caps),
getGLStencilOp(state.getStencilOpZPassBack(), caps), record, 2);
EXTStencilTwoSide.glActiveStencilFaceEXT(GL11.GL_FRONT);
applyMask(state.getStencilWriteMaskFront(), record, 1);
applyFunc(getGLStencilFunction(state.getStencilFunctionFront()), state.getStencilReferenceFront(),
state.getStencilFuncMaskFront(), record, 1);
applyOp(getGLStencilOp(state.getStencilOpFailFront(), caps),
getGLStencilOp(state.getStencilOpZFailFront(), caps),
getGLStencilOp(state.getStencilOpZPassFront(), caps), record, 1);
} else {
applyMask(state.getStencilWriteMaskFront(), record, 0);
applyFunc(getGLStencilFunction(state.getStencilFunctionFront()), state.getStencilReferenceFront(),
state.getStencilFuncMaskFront(), record, 0);
applyOp(getGLStencilOp(state.getStencilOpFailFront(), caps),
getGLStencilOp(state.getStencilOpZFailFront(), caps),
getGLStencilOp(state.getStencilOpZPassFront(), caps), record, 0);
}
}
if (!record.isValid()) {
record.validate();
}
}
private static int getGLStencilFunction(final StencilFunction function) {
switch (function) {
case Always:
return GL11.GL_ALWAYS;
case Never:
return GL11.GL_NEVER;
case EqualTo:
return GL11.GL_EQUAL;
case NotEqualTo:
return GL11.GL_NOTEQUAL;
case GreaterThan:
return GL11.GL_GREATER;
case GreaterThanOrEqualTo:
return GL11.GL_GEQUAL;
case LessThan:
return GL11.GL_LESS;
case LessThanOrEqualTo:
return GL11.GL_LEQUAL;
}
throw new IllegalArgumentException("unknown function: " + function);
}
private static int getGLStencilOp(final StencilOperation operation, final ContextCapabilities caps) {
switch (operation) {
case Keep:
return GL11.GL_KEEP;
case DecrementWrap:
if (caps.isStencilWrapSupported()) {
return EXTStencilWrap.GL_DECR_WRAP_EXT;
}
// FALLS THROUGH
case Decrement:
return GL11.GL_DECR;
case IncrementWrap:
if (caps.isStencilWrapSupported()) {
return EXTStencilWrap.GL_INCR_WRAP_EXT;
}
// FALLS THROUGH
case Increment:
return GL11.GL_INCR;
case Invert:
return GL11.GL_INVERT;
case Replace:
return GL11.GL_REPLACE;
case Zero:
return GL11.GL_ZERO;
}
throw new IllegalArgumentException("unknown operation: " + operation);
}
private static void setEnabled(final boolean enable, final boolean twoSided, final StencilStateRecord record,
final ContextCapabilities caps) {
if (record.isValid()) {
if (enable && !record.enabled) {
GL11.glEnable(GL11.GL_STENCIL_TEST);
} else if (!enable && record.enabled) {
GL11.glDisable(GL11.GL_STENCIL_TEST);
}
} else {
if (enable) {
GL11.glEnable(GL11.GL_STENCIL_TEST);
} else {
GL11.glDisable(GL11.GL_STENCIL_TEST);
}
}
setTwoSidedEnabled(enable ? twoSided : false, record, caps);
record.enabled = enable;
}
private static void setTwoSidedEnabled(final boolean enable, final StencilStateRecord record,
final ContextCapabilities caps) {
if (caps.isTwoSidedStencilSupported()) {
if (record.isValid()) {
if (enable && !record.useTwoSided) {
GL11.glEnable(EXTStencilTwoSide.GL_STENCIL_TEST_TWO_SIDE_EXT);
} else if (!enable && record.useTwoSided) {
GL11.glDisable(EXTStencilTwoSide.GL_STENCIL_TEST_TWO_SIDE_EXT);
}
} else {
if (enable) {
GL11.glEnable(EXTStencilTwoSide.GL_STENCIL_TEST_TWO_SIDE_EXT);
} else {
GL11.glDisable(EXTStencilTwoSide.GL_STENCIL_TEST_TWO_SIDE_EXT);
}
}
}
record.useTwoSided = enable;
}
private static void applyMask(final int writeMask, final StencilStateRecord record, final int face) {
// if (!record.isValid() || writeMask != record.writeMask[face]) {
GL11.glStencilMask(writeMask);
// record.writeMask[face] = writeMask;
// }
}
private static void applyFunc(final int glfunc, final int stencilRef, final int funcMask,
final StencilStateRecord record, final int face) {
// if (!record.isValid() || glfunc != record.func[face] || stencilRef != record.ref[face]
// || funcMask != record.funcMask[face]) {
GL11.glStencilFunc(glfunc, stencilRef, funcMask);
// record.func[face] = glfunc;
// record.ref[face] = stencilRef;
// record.funcMask[face] = funcMask;
// }
}
private static void applyOp(final int fail, final int zfail, final int zpass, final StencilStateRecord record,
final int face) {
// if (!record.isValid() || fail != record.fail[face] || zfail != record.zfail[face]
// || zpass != record.zpass[face]) {
GL11.glStencilOp(fail, zfail, zpass);
// record.fail[face] = fail;
// record.zfail[face] = zfail;
// record.zpass[face] = zpass;
// }
}
}