public void clearBuffers(boolean color, boolean depth, boolean stencil) {
int bits = 0;
if (color) {
// See explanations of the depth below, we must enable color write to be able to clear the
// color buffer
if (context.colorWriteEnabled == false) {
glColorMask(true, true, true, true);
context.colorWriteEnabled = true;
}
bits = GL_COLOR_BUFFER_BIT;
}
if (depth) {
// glClear(GL_DEPTH_BUFFER_BIT) seems to not work when glDepthMask is false
// here s some link on openl board
// http://www.opengl.org/discussion_boards/ubbthreads.php?ubb=showflat&Number=257223
// if depth clear is requested, we enable the depthMask
if (context.depthWriteEnabled == false) {
glDepthMask(true);
context.depthWriteEnabled = true;
}
bits |= GL_DEPTH_BUFFER_BIT;
}
if (stencil) {
bits |= GL_STENCIL_BUFFER_BIT;
}
if (bits != 0) {
glClear(bits);
}
}
public void applyRenderState(RenderState state) {
if (state.isWireframe() && !context.wireframe) {
glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
context.wireframe = true;
} else if (!state.isWireframe() && context.wireframe) {
glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
context.wireframe = false;
}
if (state.isDepthTest() && !context.depthTestEnabled) {
glEnable(GL_DEPTH_TEST);
glDepthFunc(GL_LEQUAL);
context.depthTestEnabled = true;
} else if (!state.isDepthTest() && context.depthTestEnabled) {
glDisable(GL_DEPTH_TEST);
context.depthTestEnabled = false;
}
if (state.isAlphaTest()) {
setFixedFuncBinding(FixedFuncBinding.AlphaTestFallOff, state.getAlphaFallOff());
} else {
setFixedFuncBinding(FixedFuncBinding.AlphaTestFallOff, 0f); // disable it
}
if (state.isDepthWrite() && !context.depthWriteEnabled) {
glDepthMask(true);
context.depthWriteEnabled = true;
} else if (!state.isDepthWrite() && context.depthWriteEnabled) {
glDepthMask(false);
context.depthWriteEnabled = false;
}
if (state.isColorWrite() && !context.colorWriteEnabled) {
glColorMask(true, true, true, true);
context.colorWriteEnabled = true;
} else if (!state.isColorWrite() && context.colorWriteEnabled) {
glColorMask(false, false, false, false);
context.colorWriteEnabled = false;
}
if (state.isPointSprite()) {
logger.log(Level.WARNING, "Point Sprite unsupported!");
}
if (state.isPolyOffset()) {
if (!context.polyOffsetEnabled) {
glEnable(GL_POLYGON_OFFSET_FILL);
glPolygonOffset(state.getPolyOffsetFactor(), state.getPolyOffsetUnits());
context.polyOffsetEnabled = true;
context.polyOffsetFactor = state.getPolyOffsetFactor();
context.polyOffsetUnits = state.getPolyOffsetUnits();
} else {
if (state.getPolyOffsetFactor() != context.polyOffsetFactor
|| state.getPolyOffsetUnits() != context.polyOffsetUnits) {
glPolygonOffset(state.getPolyOffsetFactor(), state.getPolyOffsetUnits());
context.polyOffsetFactor = state.getPolyOffsetFactor();
context.polyOffsetUnits = state.getPolyOffsetUnits();
}
}
} else {
if (context.polyOffsetEnabled) {
glDisable(GL_POLYGON_OFFSET_FILL);
context.polyOffsetEnabled = false;
context.polyOffsetFactor = 0;
context.polyOffsetUnits = 0;
}
}
if (state.getFaceCullMode() != context.cullMode) {
if (state.getFaceCullMode() == RenderState.FaceCullMode.Off) {
glDisable(GL_CULL_FACE);
} else {
glEnable(GL_CULL_FACE);
}
switch (state.getFaceCullMode()) {
case Off:
break;
case Back:
glCullFace(GL_BACK);
break;
case Front:
glCullFace(GL_FRONT);
break;
case FrontAndBack:
glCullFace(GL_FRONT_AND_BACK);
break;
default:
throw new UnsupportedOperationException(
"Unrecognized face cull mode: " + state.getFaceCullMode());
}
context.cullMode = state.getFaceCullMode();
}
if (state.getBlendMode() != context.blendMode) {
if (state.getBlendMode() == RenderState.BlendMode.Off) {
glDisable(GL_BLEND);
} else {
glEnable(GL_BLEND);
switch (state.getBlendMode()) {
case Off:
break;
case Additive:
glBlendFunc(GL_ONE, GL_ONE);
break;
case AlphaAdditive:
glBlendFunc(GL_SRC_ALPHA, GL_ONE);
break;
case Color:
glBlendFunc(GL_ONE, GL_ONE_MINUS_SRC_COLOR);
break;
case Alpha:
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
break;
case PremultAlpha:
glBlendFunc(GL_ONE, GL_ONE_MINUS_SRC_ALPHA);
break;
case Modulate:
glBlendFunc(GL_DST_COLOR, GL_ZERO);
break;
case ModulateX2:
glBlendFunc(GL_DST_COLOR, GL_SRC_COLOR);
break;
default:
throw new UnsupportedOperationException(
"Unrecognized blend mode: " + state.getBlendMode());
}
}
context.blendMode = state.getBlendMode();
}
if (state.isStencilTest()) {
throw new UnsupportedOperationException(
"OpenGL 1.1 doesn't support two sided stencil operations.");
}
}