reactos/dll/opengl/mesa/main/blend.c

353 lines
9.1 KiB
C

/**
* \file blend.c
* Blending operations.
*/
/*
* Mesa 3-D graphics library
* Version: 6.5.1
*
* Copyright (C) 1999-2006 Brian Paul All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a
* copy of this software and associated documentation files (the "Software"),
* to deal in the Software without restriction, including without limitation
* the rights to use, copy, modify, merge, publish, distribute, sublicense,
* and/or sell copies of the Software, and to permit persons to whom the
* Software is furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
* AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#include <precomp.h>
/**
* Check if given blend source factor is legal.
* \return GL_TRUE if legal, GL_FALSE otherwise.
*/
static GLboolean
legal_src_factor(const struct gl_context *ctx, GLenum factor)
{
switch (factor) {
case GL_SRC_COLOR:
case GL_ONE_MINUS_SRC_COLOR:
return ctx->Extensions.NV_blend_square;
case GL_ZERO:
case GL_ONE:
case GL_DST_COLOR:
case GL_ONE_MINUS_DST_COLOR:
case GL_SRC_ALPHA:
case GL_ONE_MINUS_SRC_ALPHA:
case GL_DST_ALPHA:
case GL_ONE_MINUS_DST_ALPHA:
case GL_SRC_ALPHA_SATURATE:
case GL_CONSTANT_COLOR:
case GL_ONE_MINUS_CONSTANT_COLOR:
case GL_CONSTANT_ALPHA:
case GL_ONE_MINUS_CONSTANT_ALPHA:
return GL_TRUE;
default:
return GL_FALSE;
}
}
/**
* Check if given blend destination factor is legal.
* \return GL_TRUE if legal, GL_FALSE otherwise.
*/
static GLboolean
legal_dst_factor(const struct gl_context *ctx, GLenum factor)
{
switch (factor) {
case GL_DST_COLOR:
case GL_ONE_MINUS_DST_COLOR:
return ctx->Extensions.NV_blend_square;
case GL_ZERO:
case GL_ONE:
case GL_SRC_COLOR:
case GL_ONE_MINUS_SRC_COLOR:
case GL_SRC_ALPHA:
case GL_ONE_MINUS_SRC_ALPHA:
case GL_DST_ALPHA:
case GL_ONE_MINUS_DST_ALPHA:
case GL_CONSTANT_COLOR:
case GL_ONE_MINUS_CONSTANT_COLOR:
case GL_CONSTANT_ALPHA:
case GL_ONE_MINUS_CONSTANT_ALPHA:
return GL_TRUE;
default:
return GL_FALSE;
}
}
/**
* Check if src/dest RGB/A blend factors are legal. If not generate
* a GL error.
* \return GL_TRUE if factors are legal, GL_FALSE otherwise.
*/
static GLboolean
validate_blend_factors(struct gl_context *ctx, const char *func,
GLenum srcfactor, GLenum dstfactor)
{
if (!legal_src_factor(ctx, srcfactor)) {
_mesa_error(ctx, GL_INVALID_ENUM,
"%s(sfactorRGB = %s)", func,
_mesa_lookup_enum_by_nr(srcfactor));
return GL_FALSE;
}
if (!legal_dst_factor(ctx, dstfactor)) {
_mesa_error(ctx, GL_INVALID_ENUM,
"%s(dfactorRGB = %s)", func,
_mesa_lookup_enum_by_nr(dstfactor));
return GL_FALSE;
}
return GL_TRUE;
}
/**
* Specify the blending operation.
*
* \param sfactor source factor operator.
* \param dfactor destination factor operator.
*
* \sa glBlendFunc
*/
void GLAPIENTRY
_mesa_BlendFunc( GLenum sfactor, GLenum dfactor )
{
GET_CURRENT_CONTEXT(ctx);
ASSERT_OUTSIDE_BEGIN_END(ctx);
if (MESA_VERBOSE & VERBOSE_API)
_mesa_debug(ctx, "glBlendFunc %s %s\n",
_mesa_lookup_enum_by_nr(sfactor),
_mesa_lookup_enum_by_nr(dfactor));
if (!validate_blend_factors(ctx, "glBlendFunc", sfactor, dfactor)) {
return;
}
if (ctx->Color.SrcFactor == sfactor &&
ctx->Color.DstFactor == dfactor) {
return;
}
FLUSH_VERTICES(ctx, _NEW_COLOR);
ctx->Color.SrcFactor = sfactor;
ctx->Color.DstFactor = dfactor;
}
/**
* Specify the alpha test function.
*
* \param func alpha comparison function.
* \param ref reference value.
*
* Verifies the parameters and updates gl_colorbuffer_attrib.
* On a change, flushes the vertices and notifies the driver via
* dd_function_table::AlphaFunc callback.
*/
void GLAPIENTRY
_mesa_AlphaFunc( GLenum func, GLclampf ref )
{
GET_CURRENT_CONTEXT(ctx);
ASSERT_OUTSIDE_BEGIN_END(ctx);
if (MESA_VERBOSE & VERBOSE_API)
_mesa_debug(ctx, "glAlphaFunc(%s, %f)\n",
_mesa_lookup_enum_by_nr(func), ref);
switch (func) {
case GL_NEVER:
case GL_LESS:
case GL_EQUAL:
case GL_LEQUAL:
case GL_GREATER:
case GL_NOTEQUAL:
case GL_GEQUAL:
case GL_ALWAYS:
if (ctx->Color.AlphaFunc == func && ctx->Color.AlphaRef == ref)
return; /* no change */
FLUSH_VERTICES(ctx, _NEW_COLOR);
ctx->Color.AlphaFunc = func;
ctx->Color.AlphaRef = ref;
if (ctx->Driver.AlphaFunc)
ctx->Driver.AlphaFunc(ctx, func, ctx->Color.AlphaRef);
return;
default:
_mesa_error( ctx, GL_INVALID_ENUM, "glAlphaFunc(func)" );
return;
}
}
/**
* Specify a logic pixel operation for color index rendering.
*
* \param opcode operation.
*
* Verifies that \p opcode is a valid enum and updates
gl_colorbuffer_attrib::LogicOp.
* On a change, flushes the vertices and notifies the driver via the
* dd_function_table::LogicOpcode callback.
*/
void GLAPIENTRY
_mesa_LogicOp( GLenum opcode )
{
GET_CURRENT_CONTEXT(ctx);
ASSERT_OUTSIDE_BEGIN_END(ctx);
if (MESA_VERBOSE & VERBOSE_API)
_mesa_debug(ctx, "glLogicOp(%s)\n", _mesa_lookup_enum_by_nr(opcode));
switch (opcode) {
case GL_CLEAR:
case GL_SET:
case GL_COPY:
case GL_COPY_INVERTED:
case GL_NOOP:
case GL_INVERT:
case GL_AND:
case GL_NAND:
case GL_OR:
case GL_NOR:
case GL_XOR:
case GL_EQUIV:
case GL_AND_REVERSE:
case GL_AND_INVERTED:
case GL_OR_REVERSE:
case GL_OR_INVERTED:
break;
default:
_mesa_error( ctx, GL_INVALID_ENUM, "glLogicOp" );
return;
}
if (ctx->Color.LogicOp == opcode)
return;
FLUSH_VERTICES(ctx, _NEW_COLOR);
ctx->Color.LogicOp = opcode;
if (ctx->Driver.LogicOpcode)
ctx->Driver.LogicOpcode( ctx, opcode );
}
#if _HAVE_FULL_GL
void GLAPIENTRY
_mesa_IndexMask( GLuint mask )
{
GET_CURRENT_CONTEXT(ctx);
ASSERT_OUTSIDE_BEGIN_END(ctx);
if (ctx->Color.IndexMask == mask)
return;
FLUSH_VERTICES(ctx, _NEW_COLOR);
ctx->Color.IndexMask = mask;
}
#endif
/**
* Enable or disable writing of frame buffer color components.
*
* \param red whether to mask writing of the red color component.
* \param green whether to mask writing of the green color component.
* \param blue whether to mask writing of the blue color component.
* \param alpha whether to mask writing of the alpha color component.
*
* \sa glColorMask().
*
* Sets the appropriate value of gl_colorbuffer_attrib::ColorMask. On a
* change, flushes the vertices and notifies the driver via the
* dd_function_table::ColorMask callback.
*/
void GLAPIENTRY
_mesa_ColorMask( GLboolean red, GLboolean green,
GLboolean blue, GLboolean alpha )
{
GET_CURRENT_CONTEXT(ctx);
GLubyte tmp[4];
ASSERT_OUTSIDE_BEGIN_END(ctx);
if (MESA_VERBOSE & VERBOSE_API)
_mesa_debug(ctx, "glColorMask(%d, %d, %d, %d)\n",
red, green, blue, alpha);
/* Shouldn't have any information about channel depth in core mesa
* -- should probably store these as the native booleans:
*/
tmp[RCOMP] = red ? 0xff : 0x0;
tmp[GCOMP] = green ? 0xff : 0x0;
tmp[BCOMP] = blue ? 0xff : 0x0;
tmp[ACOMP] = alpha ? 0xff : 0x0;
if (!TEST_EQ_4V(tmp, ctx->Color.ColorMask)) {
FLUSH_VERTICES(ctx, _NEW_COLOR);
COPY_4UBV(ctx->Color.ColorMask, tmp);
}
if (ctx->Driver.ColorMask)
ctx->Driver.ColorMask( ctx, red, green, blue, alpha );
}
/**********************************************************************/
/** \name Initialization */
/*@{*/
/**
* Initialization of the context's Color attribute group.
*
* \param ctx GL context.
*
* Initializes the related fields in the context color attribute group,
* __struct gl_contextRec::Color.
*/
void _mesa_init_color( struct gl_context * ctx )
{
/* Color buffer group */
ctx->Color.IndexMask = ~0u;
memset(ctx->Color.ColorMask, 0xff, sizeof(ctx->Color.ColorMask));
ctx->Color.ClearIndex = 0;
ASSIGN_4V( ctx->Color.ClearColor.f, 0, 0, 0, 0 );
ctx->Color.AlphaEnabled = GL_FALSE;
ctx->Color.AlphaFunc = GL_ALWAYS;
ctx->Color.AlphaRef = 0;
ctx->Color.BlendEnabled = 0x0;
ctx->Color.SrcFactor = GL_ONE;
ctx->Color.DstFactor = GL_ZERO;
ctx->Color.IndexLogicOpEnabled = GL_FALSE;
ctx->Color.ColorLogicOpEnabled = GL_FALSE;
ctx->Color.LogicOp = GL_COPY;
ctx->Color.DitherFlag = GL_TRUE;
if (ctx->Visual.doubleBufferMode) {
ctx->Color.DrawBuffer = GL_BACK;
}
else {
ctx->Color.DrawBuffer = GL_FRONT;
}
}
/*@}*/