mutter/cogl/cogl-depth-state.h
Robert Bragg a0441778ad This re-licenses Cogl 1.18 under the MIT license
Since the Cogl 1.18 branch is actively maintained in parallel with the
master branch; this is a counter part to commit 1b83ef938fc16b which
re-licensed the master branch to use the MIT license.

This re-licensing is a follow up to the proposal that was sent to the
Cogl mailing list:
http://lists.freedesktop.org/archives/cogl/2013-December/001465.html

Note: there was a copyright assignment policy in place for Clutter (and
therefore Cogl which was part of Clutter at the time) until the 11th of
June 2010 and so we only checked the details after that point (commit
0bbf50f905)

For each file, authors were identified via this Git command:
$ git blame -p -C -C -C20 -M -M10  0bbf50f905..HEAD

We received blanket approvals for re-licensing all Red Hat and Collabora
contributions which reduced how many people needed to be contacted
individually:
- http://lists.freedesktop.org/archives/cogl/2013-December/001470.html
- http://lists.freedesktop.org/archives/cogl/2014-January/001536.html

Individual approval requests were sent to all the other identified authors
who all confirmed the re-license on the Cogl mailinglist:
http://lists.freedesktop.org/archives/cogl/2014-January

As well as updating the copyright header in all sources files, the
COPYING file has been updated to reflect the license change and also
document the other licenses used in Cogl such as the SGI Free Software
License B, version 2.0 and the 3-clause BSD license.

This patch was not simply cherry-picked from master; but the same
methodology was used to check the source files.
2014-02-22 02:02:53 +00:00

271 lines
8.3 KiB
C

/*
* Cogl
*
* A Low Level GPU Graphics and Utilities API
*
* Copyright (C) 2011 Intel Corporation.
*
* 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.
*
* Authors:
* Robert Bragg <robert@linux.intel.com>
*
*/
#if !defined(__COGL_H_INSIDE__) && !defined(COGL_COMPILATION)
#error "Only <cogl/cogl.h> can be included directly."
#endif
#ifndef __COGL_DEPTH_STATE_H__
#define __COGL_DEPTH_STATE_H__
COGL_BEGIN_DECLS
/**
* SECTION:cogl-depth-state
* @short_description: Functions for describing the depth testing
* state of your GPU.
*/
/**
* CoglDepthState:
*
* Since: 2.0
*/
typedef struct {
/*< private >*/
uint32_t COGL_PRIVATE (magic);
CoglBool COGL_PRIVATE (test_enabled);
CoglDepthTestFunction COGL_PRIVATE (test_function);
CoglBool COGL_PRIVATE (write_enabled);
float COGL_PRIVATE (range_near);
float COGL_PRIVATE (range_far);
uint32_t COGL_PRIVATE (padding0);
uint32_t COGL_PRIVATE (padding1);
uint32_t COGL_PRIVATE (padding2);
uint32_t COGL_PRIVATE (padding3);
uint32_t COGL_PRIVATE (padding4);
uint32_t COGL_PRIVATE (padding5);
uint32_t COGL_PRIVATE (padding6);
uint32_t COGL_PRIVATE (padding7);
uint32_t COGL_PRIVATE (padding8);
uint32_t COGL_PRIVATE (padding9);
} CoglDepthState;
/**
* cogl_depth_state_init:
* @state: A #CoglDepthState struct
*
* Initializes the members of @state to their default values.
*
* You should never pass an un initialized #CoglDepthState structure
* to cogl_pipeline_set_depth_state().
*
* Since: 2.0
* Stability: Unstable
*/
void
cogl_depth_state_init (CoglDepthState *state);
/**
* cogl_depth_state_set_test_enabled:
* @state: A #CoglDepthState struct
* @enable: The enable state you want
*
* Enables or disables depth testing according to the value of
* @enable.
*
* If depth testing is enable then the #CoglDepthTestFunction set
* using cogl_depth_state_set_test_function() us used to evaluate
* the depth value of incoming fragments against the corresponding
* value stored in the current depth buffer, and if the test passes
* then the fragments depth value is used to update the depth buffer.
* (unless you have disabled depth writing via
* cogl_depth_state_set_write_enabled())
*
* By default depth testing is disabled.
*
* NB: this won't directly affect the state of the GPU. You have
* to then set the state on a #CoglPipeline using
* cogl_pipeline_set_depth_state()
*
* Since: 2.0
* Stability: Unstable
*/
void
cogl_depth_state_set_test_enabled (CoglDepthState *state,
CoglBool enable);
/**
* cogl_depth_state_get_test_enabled:
* @state: A #CoglDepthState struct
*
* Gets the current depth test enabled state as previously set by
* cogl_depth_state_set_test_enabled().
*
* Returns: The pipeline's current depth test enabled state.
* Since: 2.0
* Stability: Unstable
*/
CoglBool
cogl_depth_state_get_test_enabled (CoglDepthState *state);
/**
* cogl_depth_state_set_write_enabled:
* @state: A #CoglDepthState struct
* @enable: The enable state you want
*
* Enables or disables depth buffer writing according to the value of
* @enable. Normally when depth testing is enabled and the comparison
* between a fragment's depth value and the corresponding depth buffer
* value passes then the fragment's depth is written to the depth
* buffer unless writing is disabled here.
*
* By default depth writing is enabled
*
* NB: this won't directly affect the state of the GPU. You have
* to then set the state on a #CoglPipeline using
* cogl_pipeline_set_depth_state()
*
* Since: 2.0
* Stability: Unstable
*/
void
cogl_depth_state_set_write_enabled (CoglDepthState *state,
CoglBool enable);
/**
* cogl_depth_state_get_write_enabled:
* @state: A #CoglDepthState struct
*
* Gets the depth writing enable state as set by the corresponding
* cogl_depth_state_set_write_enabled().
*
* Returns: The current depth writing enable state
* Since: 2.0
* Stability: Unstable
*/
CoglBool
cogl_depth_state_get_write_enabled (CoglDepthState *state);
/**
* cogl_depth_state_set_test_function:
* @state: A #CoglDepthState struct
* @function: The #CoglDepthTestFunction to set
*
* Sets the #CoglDepthTestFunction used to compare the depth value of
* an incoming fragment against the corresponding value in the current
* depth buffer.
*
* By default the depth test function is %COGL_DEPTH_TEST_FUNCTION_LESS
*
* NB: this won't directly affect the state of the GPU. You have
* to then set the state on a #CoglPipeline using
* cogl_pipeline_set_depth_state()
*
* Since: 2.0
* Stability: Unstable
*/
void
cogl_depth_state_set_test_function (CoglDepthState *state,
CoglDepthTestFunction function);
/**
* cogl_depth_state_get_test_function:
* @state: A #CoglDepthState struct
*
* Gets the current depth test enable state as previously set via
* cogl_depth_state_set_test_enabled().
*
* Returns: The current depth test enable state.
* Since: 2.0
* Stability: Unstable
*/
CoglDepthTestFunction
cogl_depth_state_get_test_function (CoglDepthState *state);
/**
* cogl_depth_state_set_range:
* @state: A #CoglDepthState object
* @near_val: The near component of the desired depth range which will be
* clamped to the range [0, 1]
* @far_val: The far component of the desired depth range which will be
* clamped to the range [0, 1]
*
* Sets the range to map depth values in normalized device coordinates
* to before writing out to a depth buffer.
*
* After your geometry has be transformed, clipped and had perspective
* division applied placing it in normalized device
* coordinates all depth values between the near and far z clipping
* planes are in the range -1 to 1. Before writing any depth value to
* the depth buffer though the value is mapped into the range [0, 1].
*
* With this function you can change the range which depth values are
* mapped too although the range must still lye within the range [0,
* 1].
*
* If your driver does not support this feature (for example you are
* using GLES 1 drivers) then if you don't use the default range
* values you will get an error reported when calling
* cogl_pipeline_set_depth_state (). You can check ahead of time for
* the %COGL_FEATURE_ID_DEPTH_RANGE feature with
* cogl_has_feature() to know if this function will succeed.
*
* By default normalized device coordinate depth values are mapped to
* the full range of depth buffer values, [0, 1].
*
* NB: this won't directly affect the state of the GPU. You have
* to then set the state on a #CoglPipeline using
* cogl_pipeline_set_depth_state().
*
* Since: 2.0
* Stability: Unstable
*/
void
cogl_depth_state_set_range (CoglDepthState *state,
float near_val,
float far_val);
/**
* cogl_depth_state_get_range:
* @state: A #CoglDepthState object
* @near_val: A pointer to store the near component of the depth range
* @far_val: A pointer to store the far component of the depth range
*
* Gets the current range to which normalized depth values are mapped
* before writing to the depth buffer. This corresponds to the range
* set with cogl_depth_state_set_range().
*
* Since: 2.0
* Stability: Unstable
*/
void
cogl_depth_state_get_range (CoglDepthState *state,
float *near_val,
float *far_val);
COGL_END_DECLS
#endif /* __COGL_DEPTH_STATE_H__ */