/*
* 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 "enums.h"
#include "macros.h"
#include "mtypes.h"
#include "viewport.h"
static void
set_viewport_no_notify(struct gl_context *ctx, unsigned idx,
GLfloat x, GLfloat y,
GLfloat width, GLfloat height)
{
/* clamp width and height to the implementation dependent range */
width = MIN2(width, (GLfloat) ctx->Const.MaxViewportWidth);
height = MIN2(height, (GLfloat) ctx->Const.MaxViewportHeight);
/* The GL_ARB_viewport_array spec says:
*
* "The location of the viewport's bottom-left corner, given by (x,y),
* are clamped to be within the implementation-dependent viewport
* bounds range. The viewport bounds range [min, max] tuple may be
* determined by calling GetFloatv with the symbolic constant
* VIEWPORT_BOUNDS_RANGE (see section 6.1)."
*/
if (ctx->Extensions.ARB_viewport_array) {
x = CLAMP(x,
ctx->Const.ViewportBounds.Min, ctx->Const.ViewportBounds.Max);
y = CLAMP(y,
ctx->Const.ViewportBounds.Min, ctx->Const.ViewportBounds.Max);
}
if (ctx->ViewportArray[idx].X == x &&
ctx->ViewportArray[idx].Width == width &&
ctx->ViewportArray[idx].Y == y &&
ctx->ViewportArray[idx].Height == height)
return;
ctx->ViewportArray[idx].X = x;
ctx->ViewportArray[idx].Width = width;
ctx->ViewportArray[idx].Y = y;
ctx->ViewportArray[idx].Height = height;
ctx->NewState |= _NEW_VIEWPORT;
}
struct gl_viewport_inputs {
GLfloat X, Y; /**< position */
GLfloat Width, Height; /**< size */
};
struct gl_depthrange_inputs {
GLdouble Near, Far; /**< Depth buffer range */
};
/**
* 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)
{
unsigned i;
GET_CURRENT_CONTEXT(ctx);
FLUSH_VERTICES(ctx, 0);
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;
}
/* The GL_ARB_viewport_array spec says:
*
* "Viewport sets the parameters for all viewports to the same values
* and is equivalent (assuming no errors are generated) to:
*
* for (uint i = 0; i < MAX_VIEWPORTS; i++)
* ViewportIndexedf(i, 1, (float)x, (float)y, (float)w, (float)h);"
*
* Set all of the viewports supported by the implementation, but only
* signal the driver once at the end.
*/
for (i = 0; i < ctx->Const.MaxViewports; i++)
set_viewport_no_notify(ctx, i, x, y, width, height);
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);
}
}
/**
* Set new viewport parameters and update derived state.
* Usually called from _mesa_Viewport().
*
* \param ctx GL context.
* \param idx Index of the viewport to be updated.
* \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, unsigned idx, GLfloat x, GLfloat y,
GLfloat width, GLfloat height)
{
set_viewport_no_notify(ctx, idx, x, y, width, height);
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);
}
}
void GLAPIENTRY
_mesa_ViewportArrayv(GLuint first, GLsizei count, const GLfloat *v)
{
int i;
const struct gl_viewport_inputs *const p = (struct gl_viewport_inputs *) v;
GET_CURRENT_CONTEXT(ctx);
if (MESA_VERBOSE & VERBOSE_API)
_mesa_debug(ctx, "glViewportArrayv %d %d\n", first, count);
if ((first + count) > ctx->Const.MaxViewports) {
_mesa_error(ctx, GL_INVALID_VALUE,
"glViewportArrayv: first (%d) + count (%d) > MaxViewports "
"(%d)",
first, count, ctx->Const.MaxViewports);
return;
}
/* Verify width & height */
for (i = 0; i < count; i++) {
if (p[i].Width < 0 || p[i].Height < 0) {
_mesa_error(ctx, GL_INVALID_VALUE,
"glViewportArrayv: index (%d) width or height < 0 "
"(%f, %f)",
i + first, p[i].Width, p[i].Height);
return;
}
}
for (i = 0; i < count; i++)
set_viewport_no_notify(ctx, i + first,
p[i].X, p[i].Y,
p[i].Width, p[i].Height);
if (ctx->Driver.Viewport)
ctx->Driver.Viewport(ctx);
}
static void
ViewportIndexedf(GLuint index, GLfloat x, GLfloat y,
GLfloat w, GLfloat h, const char *function)
{
GET_CURRENT_CONTEXT(ctx);
if (MESA_VERBOSE & VERBOSE_API)
_mesa_debug(ctx, "%s(%d, %f, %f, %f, %f)\n",
function, index, x, y, w, h);
if (index >= ctx->Const.MaxViewports) {
_mesa_error(ctx, GL_INVALID_VALUE,
"%s: index (%d) >= MaxViewports (%d)",
function, index, ctx->Const.MaxViewports);
return;
}
/* Verify width & height */
if (w < 0 || h < 0) {
_mesa_error(ctx, GL_INVALID_VALUE,
"%s: index (%d) width or height < 0 (%f, %f)",
function, index, w, h);
return;
}
_mesa_set_viewport(ctx, index, x, y, w, h);
}
void GLAPIENTRY
_mesa_ViewportIndexedf(GLuint index, GLfloat x, GLfloat y,
GLfloat w, GLfloat h)
{
ViewportIndexedf(index, x, y, w, h, "glViewportIndexedf");
}
void GLAPIENTRY
_mesa_ViewportIndexedfv(GLuint index, const GLfloat *v)
{
ViewportIndexedf(index, v[0], v[1], v[2], v[3], "glViewportIndexedfv");
}
static void
set_depth_range_no_notify(struct gl_context *ctx, unsigned idx,
GLclampd nearval, GLclampd farval)
{
if (ctx->ViewportArray[idx].Near == nearval &&
ctx->ViewportArray[idx].Far == farval)
return;
ctx->ViewportArray[idx].Near = CLAMP(nearval, 0.0, 1.0);
ctx->ViewportArray[idx].Far = CLAMP(farval, 0.0, 1.0);
ctx->NewState |= _NEW_VIEWPORT;
}
void
_mesa_set_depth_range(struct gl_context *ctx, unsigned idx,
GLclampd nearval, GLclampd farval)
{
set_depth_range_no_notify(ctx, idx, nearval, farval);
if (ctx->Driver.DepthRange)
ctx->Driver.DepthRange(ctx);
}
/**
* 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)
{
unsigned i;
GET_CURRENT_CONTEXT(ctx);
FLUSH_VERTICES(ctx, 0);
if (MESA_VERBOSE&VERBOSE_API)
_mesa_debug(ctx, "glDepthRange %f %f\n", nearval, farval);
/* The GL_ARB_viewport_array spec says:
*
* "DepthRange sets the depth range for all viewports to the same
* values and is equivalent (assuming no errors are generated) to:
*
* for (uint i = 0; i < MAX_VIEWPORTS; i++)
* DepthRangeIndexed(i, n, f);"
*
* Set the depth range for all of the viewports supported by the
* implementation, but only signal the driver once at the end.
*/
for (i = 0; i < ctx->Const.MaxViewports; i++)
set_depth_range_no_notify(ctx, i, nearval, farval);
if (ctx->Driver.DepthRange) {
ctx->Driver.DepthRange(ctx);
}
}
void GLAPIENTRY
_mesa_DepthRangef(GLclampf nearval, GLclampf farval)
{
_mesa_DepthRange(nearval, farval);
}
/**
* Update a range DepthRange values
*
* \param first starting array index
* \param count count of DepthRange items to update
* \param v pointer to memory containing
* GLclampd near and far clip-plane values
*/
void GLAPIENTRY
_mesa_DepthRangeArrayv(GLuint first, GLsizei count, const GLclampd *v)
{
int i;
const struct gl_depthrange_inputs *const p =
(struct gl_depthrange_inputs *) v;
GET_CURRENT_CONTEXT(ctx);
if (MESA_VERBOSE & VERBOSE_API)
_mesa_debug(ctx, "glDepthRangeArrayv %d %d\n", first, count);
if ((first + count) > ctx->Const.MaxViewports) {
_mesa_error(ctx, GL_INVALID_VALUE,
"glDepthRangev: first (%d) + count (%d) >= MaxViewports (%d)",
first, count, ctx->Const.MaxViewports);
return;
}
for (i = 0; i < count; i++)
set_depth_range_no_notify(ctx, i + first, p[i].Near, p[i].Far);
if (ctx->Driver.DepthRange)
ctx->Driver.DepthRange(ctx);
}
/**
* Update a single DepthRange
*
* \param index array index to update
* \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_DepthRangeIndexed(GLuint index, GLclampd nearval, GLclampd farval)
{
GET_CURRENT_CONTEXT(ctx);
if (MESA_VERBOSE & VERBOSE_API)
_mesa_debug(ctx, "glDepthRangeIndexed(%d, %f, %f)\n",
index, nearval, farval);
if (index >= ctx->Const.MaxViewports) {
_mesa_error(ctx, GL_INVALID_VALUE,
"glDepthRangeIndexed: index (%d) >= MaxViewports (%d)",
index, ctx->Const.MaxViewports);
return;
}
_mesa_set_depth_range(ctx, index, nearval, farval);
}
/**
* Initialize the context viewport attribute group.
* \param ctx the GL context.
*/
void _mesa_init_viewport(struct gl_context *ctx)
{
unsigned i;
ctx->Transform.ClipOrigin = GL_LOWER_LEFT;
ctx->Transform.ClipDepthMode = GL_NEGATIVE_ONE_TO_ONE;
/* Note: ctx->Const.MaxViewports may not have been set by the driver yet,
* so just initialize all of them.
*/
for (i = 0; i < MAX_VIEWPORTS; i++) {
/* Viewport group */
ctx->ViewportArray[i].X = 0;
ctx->ViewportArray[i].Y = 0;
ctx->ViewportArray[i].Width = 0;
ctx->ViewportArray[i].Height = 0;
ctx->ViewportArray[i].Near = 0.0;
ctx->ViewportArray[i].Far = 1.0;
}
}
extern void GLAPIENTRY
_mesa_ClipControl(GLenum origin, GLenum depth)
{
GET_CURRENT_CONTEXT(ctx);
if (MESA_VERBOSE&VERBOSE_API)
_mesa_debug(ctx, "glClipControl(%s, %s)\n",
_mesa_lookup_enum_by_nr(origin),
_mesa_lookup_enum_by_nr(depth));
ASSERT_OUTSIDE_BEGIN_END(ctx);
if (!ctx->Extensions.ARB_clip_control) {
_mesa_error(ctx, GL_INVALID_OPERATION, "glClipControl");
return;
}
if (origin != GL_LOWER_LEFT && origin != GL_UPPER_LEFT) {
_mesa_error(ctx, GL_INVALID_ENUM, "glClipControl");
return;
}
if (depth != GL_NEGATIVE_ONE_TO_ONE && depth != GL_ZERO_TO_ONE) {
_mesa_error(ctx, GL_INVALID_ENUM, "glClipControl");
return;
}
if (ctx->Transform.ClipOrigin == origin &&
ctx->Transform.ClipDepthMode == depth)
return;
/* Affects transform state and the viewport transform */
FLUSH_VERTICES(ctx, _NEW_TRANSFORM | _NEW_VIEWPORT);
if (ctx->Transform.ClipOrigin != origin) {
ctx->Transform.ClipOrigin = origin;
/* Affects the winding order of the front face. */
ctx->NewState |= _NEW_POLYGON;
if (ctx->Driver.FrontFace)
ctx->Driver.FrontFace(ctx, ctx->Polygon.FrontFace);
}
if (ctx->Transform.ClipDepthMode != depth) {
ctx->Transform.ClipDepthMode = depth;
if (ctx->Driver.DepthRange)
ctx->Driver.DepthRange(ctx);
}
}
/**
* Computes the scaling and the translation part of the
* viewport transform matrix of the \param i-th viewport
* and writes that into \param scale and \param translate.
*/
void
_mesa_get_viewport_xform(struct gl_context *ctx, unsigned i,
double scale[3], double translate[3])
{
double x = ctx->ViewportArray[i].X;
double y = ctx->ViewportArray[i].Y;
double half_width = 0.5*ctx->ViewportArray[i].Width;
double half_height = 0.5*ctx->ViewportArray[i].Height;
double n = ctx->ViewportArray[i].Near;
double f = ctx->ViewportArray[i].Far;
scale[0] = half_width;
translate[0] = half_width + x;
if (ctx->Transform.ClipOrigin == GL_UPPER_LEFT) {
scale[1] = -half_height;
translate[1] = half_height - y;
} else {
scale[1] = half_height;
translate[1] = half_height + y;
}
if (ctx->Transform.ClipDepthMode == GL_NEGATIVE_ONE_TO_ONE) {
scale[2] = 0.5*(f - n);
translate[2] = 0.5*(n + f);
} else {
scale[2] = f - n;
translate[2] = n;
}
}