/*
* Mesa 3-D graphics library
*
* Copyright (C) 2009 VMware, Inc. 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
* THE AUTHORS OR COPYRIGHT HOLDERS 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.
*/
/**
* \file viewport.c
* glViewport and glDepthRange functions.
*/
#include "context.h"
#include "macros.h"
#include "mtypes.h"
#include "viewport.h"
/**
* Set the viewport.
* \sa Called via glViewport() or display list execution.
*
* Flushes the vertices and calls _mesa_set_viewport() with the given
* parameters.
*/
void GLAPIENTRY
_mesa_Viewport(GLint x, GLint y, GLsizei width, GLsizei height)
{
GET_CURRENT_CONTEXT(ctx);
FLUSH_VERTICES(ctx, 0);
_mesa_set_viewport(ctx, x, y, width, height);
}
/**
* Set new viewport parameters and update derived state (the _WindowMap
* matrix). Usually called from _mesa_Viewport().
*
* \param ctx GL context.
* \param x, y coordinates of the lower left corner of the viewport rectangle.
* \param width width of the viewport rectangle.
* \param height height of the viewport rectangle.
*/
void
_mesa_set_viewport(struct gl_context *ctx, GLint x, GLint y,
GLsizei width, GLsizei height)
{
if (MESA_VERBOSE & VERBOSE_API)
_mesa_debug(ctx, "glViewport %d %d %d %d\n", x, y, width, height);
if (width < 0 || height < 0) {
_mesa_error(ctx, GL_INVALID_VALUE,
"glViewport(%d, %d, %d, %d)", x, y, width, height);
return;
}
/* clamp width and height to the implementation dependent range */
width = MIN2(width, (GLsizei) ctx->Const.MaxViewportWidth);
height = MIN2(height, (GLsizei) ctx->Const.MaxViewportHeight);
ctx->Viewport.X = x;
ctx->Viewport.Width = width;
ctx->Viewport.Y = y;
ctx->Viewport.Height = height;
ctx->NewState |= _NEW_VIEWPORT;
#if 1
/* XXX remove this someday. Currently the DRI drivers rely on
* the WindowMap matrix being up to date in the driver's Viewport
* and DepthRange functions.
*/
_math_matrix_viewport(&ctx->Viewport._WindowMap,
ctx->Viewport.X, ctx->Viewport.Y,
ctx->Viewport.Width, ctx->Viewport.Height,
ctx->Viewport.Near, ctx->Viewport.Far,
ctx->DrawBuffer->_DepthMaxF);
#endif
if (ctx->Driver.Viewport) {
/* Many drivers will use this call to check for window size changes
* and reallocate the z/stencil/accum/etc buffers if needed.
*/
ctx->Driver.Viewport(ctx, x, y, width, height);
}
}
/**
* Called by glDepthRange
*
* \param nearval specifies the Z buffer value which should correspond to
* the near clip plane
* \param farval specifies the Z buffer value which should correspond to
* the far clip plane
*/
void GLAPIENTRY
_mesa_DepthRange(GLclampd nearval, GLclampd farval)
{
GET_CURRENT_CONTEXT(ctx);
FLUSH_VERTICES(ctx, 0);
if (MESA_VERBOSE&VERBOSE_API)
_mesa_debug(ctx, "glDepthRange %f %f\n", nearval, farval);
if (ctx->Viewport.Near == nearval &&
ctx->Viewport.Far == farval)
return;
ctx->Viewport.Near = (GLfloat) CLAMP(nearval, 0.0, 1.0);
ctx->Viewport.Far = (GLfloat) CLAMP(farval, 0.0, 1.0);
ctx->NewState |= _NEW_VIEWPORT;
#if 1
/* XXX remove this someday. Currently the DRI drivers rely on
* the WindowMap matrix being up to date in the driver's Viewport
* and DepthRange functions.
*/
_math_matrix_viewport(&ctx->Viewport._WindowMap,
ctx->Viewport.X, ctx->Viewport.Y,
ctx->Viewport.Width, ctx->Viewport.Height,
ctx->Viewport.Near, ctx->Viewport.Far,
ctx->DrawBuffer->_DepthMaxF);
#endif
if (ctx->Driver.DepthRange) {
ctx->Driver.DepthRange(ctx, nearval, farval);
}
}
void GLAPIENTRY
_mesa_DepthRangef(GLclampf nearval, GLclampf farval)
{
_mesa_DepthRange(nearval, farval);
}
/**
* Initialize the context viewport attribute group.
* \param ctx the GL context.
*/
void _mesa_init_viewport(struct gl_context *ctx)
{
GLfloat depthMax = 65535.0F; /* sorf of arbitrary */
/* Viewport group */
ctx->Viewport.X = 0;
ctx->Viewport.Y = 0;
ctx->Viewport.Width = 0;
ctx->Viewport.Height = 0;
ctx->Viewport.Near = 0.0;
ctx->Viewport.Far = 1.0;
_math_matrix_ctr(&ctx->Viewport._WindowMap);
_math_matrix_viewport(&ctx->Viewport._WindowMap, 0, 0, 0, 0,
0.0F, 1.0F, depthMax);
}
/**
* Free the context viewport attribute group data.
* \param ctx the GL context.
*/
void _mesa_free_viewport_data(struct gl_context *ctx)
{
_math_matrix_dtr(&ctx->Viewport._WindowMap);
}