/*
* Cogl
*
* A Low Level GPU Graphics and Utilities API
*
* Copyright (C) 2007,2008,2009 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.
*
*
*/
#if !defined(__COGL_H_INSIDE__) && !defined(COGL_COMPILATION)
#error "Only <cogl/cogl.h> can be included directly."
#endif
#ifndef __COGL_PIPELINE_LAYER_STATE_H__
#define __COGL_PIPELINE_LAYER_STATE_H__
#include <cogl/cogl-pipeline.h>
#include <cogl/cogl-color.h>
#include <cogl/cogl-matrix.h>
#include <cogl/cogl-texture.h>
COGL_BEGIN_DECLS
#ifdef COGL_ENABLE_EXPERIMENTAL_API
/**
* CoglPipelineFilter:
* @COGL_PIPELINE_FILTER_NEAREST: Measuring in manhatten distance from the,
* current pixel center, use the nearest texture texel
* @COGL_PIPELINE_FILTER_LINEAR: Use the weighted average of the 4 texels
* nearest the current pixel center
* @COGL_PIPELINE_FILTER_NEAREST_MIPMAP_NEAREST: Select the mimap level whose
* texel size most closely matches the current pixel, and use the
* %COGL_PIPELINE_FILTER_NEAREST criterion
* @COGL_PIPELINE_FILTER_LINEAR_MIPMAP_NEAREST: Select the mimap level whose
* texel size most closely matches the current pixel, and use the
* %COGL_PIPELINE_FILTER_LINEAR criterion
* @COGL_PIPELINE_FILTER_NEAREST_MIPMAP_LINEAR: Select the two mimap levels
* whose texel size most closely matches the current pixel, use
* the %COGL_PIPELINE_FILTER_NEAREST criterion on each one and take
* their weighted average
* @COGL_PIPELINE_FILTER_LINEAR_MIPMAP_LINEAR: Select the two mimap levels
* whose texel size most closely matches the current pixel, use
* the %COGL_PIPELINE_FILTER_LINEAR criterion on each one and take
* their weighted average
*
* Texture filtering is used whenever the current pixel maps either to more
* than one texture element (texel) or less than one. These filter enums
* correspond to different strategies used to come up with a pixel color, by
* possibly referring to multiple neighbouring texels and taking a weighted
* average or simply using the nearest texel.
*/
typedef enum {
COGL_PIPELINE_FILTER_NEAREST = 0x2600,
COGL_PIPELINE_FILTER_LINEAR = 0x2601,
COGL_PIPELINE_FILTER_NEAREST_MIPMAP_NEAREST = 0x2700,
COGL_PIPELINE_FILTER_LINEAR_MIPMAP_NEAREST = 0x2701,
COGL_PIPELINE_FILTER_NEAREST_MIPMAP_LINEAR = 0x2702,
COGL_PIPELINE_FILTER_LINEAR_MIPMAP_LINEAR = 0x2703
} CoglPipelineFilter;
/* NB: these values come from the equivalents in gl.h */
/**
* CoglPipelineWrapMode:
* @COGL_PIPELINE_WRAP_MODE_REPEAT: The texture will be repeated. This
* is useful for example to draw a tiled background.
* @COGL_PIPELINE_WRAP_MODE_CLAMP_TO_EDGE: The coordinates outside the
* range 0→1 will sample copies of the edge pixels of the
* texture. This is useful to avoid artifacts if only one copy of
* the texture is being rendered.
* @COGL_PIPELINE_WRAP_MODE_AUTOMATIC: Cogl will try to automatically
* decide which of the above two to use. For cogl_rectangle(), it
* will use repeat mode if any of the texture coordinates are
* outside the range 0→1, otherwise it will use clamp to edge. For
* cogl_polygon() it will always use repeat mode. For
* cogl_vertex_buffer_draw() it will use repeat mode except for
* layers that have point sprite coordinate generation enabled. This
* is the default value.
*
* The wrap mode specifies what happens when texture coordinates
* outside the range 0→1 are used. Note that if the filter mode is
* anything but %COGL_PIPELINE_FILTER_NEAREST then texels outside the
* range 0→1 might be used even when the coordinate is exactly 0 or 1
* because OpenGL will try to sample neighbouring pixels. For example
* if you are trying to render the full texture then you may get
* artifacts around the edges when the pixels from the other side are
* merged in if the wrap mode is set to repeat.
*
* Since: 2.0
*/
/* GL_ALWAYS is just used here as a value that is known not to clash
* with any valid GL wrap modes
*
* XXX: keep the values in sync with the CoglPipelineWrapModeInternal
* enum so no conversion is actually needed.
*/
typedef enum {
COGL_PIPELINE_WRAP_MODE_REPEAT = 0x2901,
COGL_PIPELINE_WRAP_MODE_MIRRORED_REPEAT = 0x8370,
COGL_PIPELINE_WRAP_MODE_CLAMP_TO_EDGE = 0x812F,
COGL_PIPELINE_WRAP_MODE_AUTOMATIC = 0x0207 /* GL_ALWAYS */
} CoglPipelineWrapMode;
/* NB: these values come from the equivalents in gl.h */
/**
* cogl_pipeline_set_layer:
* @pipeline: A #CoglPipeline object
* @layer_index: the index of the layer
* @texture: a #CoglTexture for the layer object
*
* In addition to the standard OpenGL lighting model a Cogl pipeline may have
* one or more layers comprised of textures that can be blended together in
* order, with a number of different texture combine modes. This function
* defines a new texture layer.
*
* The index values of multiple layers do not have to be consecutive; it is
* only their relative order that is important.
*
* The @texture parameter can also be %NULL in which case the pipeline
* will use a default white texture. The type of the default texture
* will be the same as whatever texture was last used for the pipeline
* or %COGL_TEXTURE_TYPE_2D if none has been specified yet. To
* explicitly specify the type of default texture required, use
* cogl_pipeline_set_layer_null_texture() instead.
*
* <note>In the future, we may define other types of pipeline layers, such
* as purely GLSL based layers.</note>
*
* Since: 2.0
* Stability: unstable
*/
void
cogl_pipeline_set_layer_texture (CoglPipeline *pipeline,
int layer_index,
CoglTexture *texture);
/**
* cogl_pipeline_set_layer_null_texture:
* @pipeline: A #CoglPipeline
* @layer_index: The layer number to modify
* @texture_type: The type of the default texture to use
*
* Sets the texture for this layer to be the default texture for the
* given type. This is equivalent to calling
* cogl_pipeline_set_layer_texture() with %NULL for the texture
* argument except that you can also specify the type of default
* texture to use. The default texture is a 1x1 pixel white texture.
*
* This function is mostly useful if you want to create a base
* pipeline that you want to create multiple copies from using
* cogl_pipeline_copy(). In that case this function can be used to
* specify the texture type so that any pipeline copies can share the
* internal texture type state for efficiency.
*
* Since: 1.10
* Stability: unstable
*/
void
cogl_pipeline_set_layer_null_texture (CoglPipeline *pipeline,
int layer_index,
CoglTextureType texture_type);
/**
* cogl_pipeline_get_layer_texture:
* @pipeline: A #CoglPipeline object
* @layer_index: the index of the layer
*
* Return value: (transfer none): the texture that was set for the
* given layer of the pipeline or %NULL if no texture was set.
* Stability: unstable
* Since: 1.10
*/
CoglTexture *
cogl_pipeline_get_layer_texture (CoglPipeline *pipeline,
int layer_index);
/**
* cogl_pipeline_remove_layer:
* @pipeline: A #CoglPipeline object
* @layer_index: Specifies the layer you want to remove
*
* This function removes a layer from your pipeline
* Since: 1.10
* Stability: unstable
*/
void
cogl_pipeline_remove_layer (CoglPipeline *pipeline,
int layer_index);
/**
* cogl_pipeline_set_layer_combine:
* @pipeline: A #CoglPipeline object
* @layer_index: Specifies the layer you want define a combine function for
* @blend_string: A <link linkend="cogl-Blend-Strings">Cogl blend string</link>
* describing the desired texture combine function.
* @error: A #CoglError that may report parse errors or lack of GPU/driver
* support. May be %NULL, in which case a warning will be printed out if an
* error is encountered.
*
* If not already familiar; you can refer
* <link linkend="cogl-Blend-Strings">here</link> for an overview of what blend
* strings are and there syntax.
*
* These are all the functions available for texture combining:
* <itemizedlist>
* <listitem>REPLACE(arg0) = arg0</listitem>
* <listitem>MODULATE(arg0, arg1) = arg0 x arg1</listitem>
* <listitem>ADD(arg0, arg1) = arg0 + arg1</listitem>
* <listitem>ADD_SIGNED(arg0, arg1) = arg0 + arg1 - 0.5</listitem>
* <listitem>INTERPOLATE(arg0, arg1, arg2) = arg0 x arg2 + arg1 x (1 - arg2)</listitem>
* <listitem>SUBTRACT(arg0, arg1) = arg0 - arg1</listitem>
* <listitem>
* <programlisting>
* DOT3_RGB(arg0, arg1) = 4 x ((arg0[R] - 0.5)) * (arg1[R] - 0.5) +
* (arg0[G] - 0.5)) * (arg1[G] - 0.5) +
* (arg0[B] - 0.5)) * (arg1[B] - 0.5))
* </programlisting>
* </listitem>
* <listitem>
* <programlisting>
* DOT3_RGBA(arg0, arg1) = 4 x ((arg0[R] - 0.5)) * (arg1[R] - 0.5) +
* (arg0[G] - 0.5)) * (arg1[G] - 0.5) +
* (arg0[B] - 0.5)) * (arg1[B] - 0.5))
* </programlisting>
* </listitem>
* </itemizedlist>
*
* Refer to the
* <link linkend="cogl-Blend-String-syntax">color-source syntax</link> for
* describing the arguments. The valid source names for texture combining
* are:
* <variablelist>
* <varlistentry>
* <term>TEXTURE</term>
* <listitem>Use the color from the current texture layer</listitem>
* </varlistentry>
* <varlistentry>
* <term>TEXTURE_0, TEXTURE_1, etc</term>
* <listitem>Use the color from the specified texture layer</listitem>
* </varlistentry>
* <varlistentry>
* <term>CONSTANT</term>
* <listitem>Use the color from the constant given with
* cogl_pipeline_set_layer_combine_constant()</listitem>
* </varlistentry>
* <varlistentry>
* <term>PRIMARY</term>
* <listitem>Use the color of the pipeline as set with
* cogl_pipeline_set_color()</listitem>
* </varlistentry>
* <varlistentry>
* <term>PREVIOUS</term>
* <listitem>Either use the texture color from the previous layer, or
* if this is layer 0, use the color of the pipeline as set with
* cogl_pipeline_set_color()</listitem>
* </varlistentry>
* </variablelist>
*
* <refsect2 id="cogl-Layer-Combine-Examples">
* <title>Layer Combine Examples</title>
* <para>This is effectively what the default blending is:</para>
* <informalexample><programlisting>
* RGBA = MODULATE (PREVIOUS, TEXTURE)
* </programlisting></informalexample>
* <para>This could be used to cross-fade between two images, using
* the alpha component of a constant as the interpolator. The constant
* color is given by calling
* cogl_pipeline_set_layer_combine_constant().</para>
* <informalexample><programlisting>
* RGBA = INTERPOLATE (PREVIOUS, TEXTURE, CONSTANT[A])
* </programlisting></informalexample>
* </refsect2>
*
* <note>You can't give a multiplication factor for arguments as you can
* with blending.</note>
*
* Return value: %TRUE if the blend string was successfully parsed, and the
* described texture combining is supported by the underlying driver and
* or hardware. On failure, %FALSE is returned and @error is set
*
* Since: 2.0
* Stability: unstable
*/
CoglBool
cogl_pipeline_set_layer_combine (CoglPipeline *pipeline,
int layer_index,
const char *blend_string,
CoglError **error);
/**
* cogl_pipeline_set_layer_combine_constant:
* @pipeline: A #CoglPipeline object
* @layer_index: Specifies the layer you want to specify a constant used
* for texture combining
* @constant: The constant color you want
*
* When you are using the 'CONSTANT' color source in a layer combine
* description then you can use this function to define its value.
*
* Since: 2.0
* Stability: unstable
*/
void
cogl_pipeline_set_layer_combine_constant (CoglPipeline *pipeline,
int layer_index,
const CoglColor *constant);
/**
* cogl_pipeline_set_layer_matrix:
* @pipeline: A #CoglPipeline object
* @layer_index: the index for the layer inside @pipeline
* @matrix: the transformation matrix for the layer
*
* This function lets you set a matrix that can be used to e.g. translate
* and rotate a single layer of a pipeline used to fill your geometry.
*
* Since: 1.10
* Stability: unstable
*/
void
cogl_pipeline_set_layer_matrix (CoglPipeline *pipeline,
int layer_index,
const CoglMatrix *matrix);
/**
* cogl_pipeline_get_n_layers:
* @pipeline: A #CoglPipeline object
*
* Retrieves the number of layers defined for the given @pipeline
*
* Return value: the number of layers
*
* Since: 2.0
* Stability: unstable
*/
int
cogl_pipeline_get_n_layers (CoglPipeline *pipeline);
/**
* cogl_pipeline_set_layer_filters:
* @pipeline: A #CoglPipeline object
* @layer_index: the layer number to change.
* @min_filter: the filter used when scaling a texture down.
* @mag_filter: the filter used when magnifying a texture.
*
* Changes the decimation and interpolation filters used when a texture is
* drawn at other scales than 100%.
*
* <note>It is an error to pass anything other than
* %COGL_PIPELINE_FILTER_NEAREST or %COGL_PIPELINE_FILTER_LINEAR as
* magnification filters since magnification doesn't ever need to
* reference values stored in the mipmap chain.</note>
*
* Since: 1.10
* Stability: unstable
*/
void
cogl_pipeline_set_layer_filters (CoglPipeline *pipeline,
int layer_index,
CoglPipelineFilter min_filter,
CoglPipelineFilter mag_filter);
/**
* cogl_pipeline_get_layer_min_filter:
* @pipeline: A #CoglPipeline object
* @layer_index: the layer number to change.
*
* Retrieves the currently set minification #CoglPipelineFilter set on
* the specified layer. The miniifcation filter determines how the
* layer should be sampled when down-scaled.
*
* The default filter is %COGL_PIPELINE_FILTER_LINEAR but this can be
* changed using cogl_pipeline_set_layer_filters().
*
* Return value: The minification #CoglPipelineFilter for the
* specified layer.
* Since: 1.10
* Stability: unstable
*/
CoglPipelineFilter
cogl_pipeline_get_layer_min_filter (CoglPipeline *pipeline,
int layer_index);
/**
* cogl_pipeline_get_layer_mag_filter:
* @pipeline: A #CoglPipeline object
* @layer_index: the layer number to change.
*
* Retrieves the currently set magnification #CoglPipelineFilter set on
* the specified layer. The magnification filter determines how the
* layer should be sampled when up-scaled.
*
* The default filter is %COGL_PIPELINE_FILTER_LINEAR but this can be
* changed using cogl_pipeline_set_layer_filters().
*
* Return value: The magnification #CoglPipelineFilter for the
* specified layer.
* Since: 1.10
* Stability: unstable
*/
CoglPipelineFilter
cogl_pipeline_get_layer_mag_filter (CoglPipeline *pipeline,
int layer_index);
/**
* cogl_pipeline_set_layer_point_sprite_coords_enabled:
* @pipeline: A #CoglPipeline object
* @layer_index: the layer number to change.
* @enable: whether to enable point sprite coord generation.
* @error: A return location for a CoglError, or NULL to ignore errors.
*
* When rendering points, if @enable is %TRUE then the texture
* coordinates for this layer will be replaced with coordinates that
* vary from 0.0 to 1.0 across the primitive. The top left of the
* point will have the coordinates 0.0,0.0 and the bottom right will
* have 1.0,1.0. If @enable is %FALSE then the coordinates will be
* fixed for the entire point.
*
* This function will only work if %COGL_FEATURE_ID_POINT_SPRITE is
* available. If the feature is not available then the function will
* return %FALSE and set @error.
*
* Return value: %TRUE if the function succeeds, %FALSE otherwise.
* Since: 2.0
* Stability: unstable
*/
CoglBool
cogl_pipeline_set_layer_point_sprite_coords_enabled (CoglPipeline *pipeline,
int layer_index,
CoglBool enable,
CoglError **error);
/**
* cogl_pipeline_get_layer_point_sprite_coords_enabled:
* @pipeline: A #CoglPipeline object
* @layer_index: the layer number to check.
*
* Gets whether point sprite coordinate generation is enabled for this
* texture layer.
*
* Return value: whether the texture coordinates will be replaced with
* point sprite coordinates.
*
* Since: 2.0
* Stability: unstable
*/
CoglBool
cogl_pipeline_get_layer_point_sprite_coords_enabled (CoglPipeline *pipeline,
int layer_index);
/**
* cogl_pipeline_get_layer_wrap_mode_s:
* @pipeline: A #CoglPipeline object
* @layer_index: the layer number to change.
*
* Returns the wrap mode for the 's' coordinate of texture lookups on this
* layer.
*
* Return value: the wrap mode for the 's' coordinate of texture lookups on
* this layer.
*
* Since: 1.6
* Stability: unstable
*/
CoglPipelineWrapMode
cogl_pipeline_get_layer_wrap_mode_s (CoglPipeline *pipeline,
int layer_index);
/**
* cogl_pipeline_set_layer_wrap_mode_s:
* @pipeline: A #CoglPipeline object
* @layer_index: the layer number to change.
* @mode: the new wrap mode
*
* Sets the wrap mode for the 's' coordinate of texture lookups on this layer.
*
* Since: 2.0
* Stability: unstable
*/
void
cogl_pipeline_set_layer_wrap_mode_s (CoglPipeline *pipeline,
int layer_index,
CoglPipelineWrapMode mode);
/**
* cogl_pipeline_get_layer_wrap_mode_t:
* @pipeline: A #CoglPipeline object
* @layer_index: the layer number to change.
*
* Returns the wrap mode for the 't' coordinate of texture lookups on this
* layer.
*
* Return value: the wrap mode for the 't' coordinate of texture lookups on
* this layer.
*
* Since: 1.6
* Stability: unstable
*/
CoglPipelineWrapMode
cogl_pipeline_get_layer_wrap_mode_t (CoglPipeline *pipeline,
int layer_index);
/**
* cogl_pipeline_set_layer_wrap_mode_t:
* @pipeline: A #CoglPipeline object
* @layer_index: the layer number to change.
* @mode: the new wrap mode
*
* Sets the wrap mode for the 't' coordinate of texture lookups on this layer.
*
* Since: 2.0
* Stability: unstable
*/
void
cogl_pipeline_set_layer_wrap_mode_t (CoglPipeline *pipeline,
int layer_index,
CoglPipelineWrapMode mode);
/**
* cogl_pipeline_get_layer_wrap_mode_p:
* @pipeline: A #CoglPipeline object
* @layer_index: the layer number to change.
*
* Returns the wrap mode for the 'p' coordinate of texture lookups on this
* layer.
*
* Return value: the wrap mode for the 'p' coordinate of texture lookups on
* this layer.
*
* Since: 1.6
* Stability: unstable
*/
CoglPipelineWrapMode
cogl_pipeline_get_layer_wrap_mode_p (CoglPipeline *pipeline,
int layer_index);
/**
* cogl_pipeline_set_layer_wrap_mode_p:
* @pipeline: A #CoglPipeline object
* @layer_index: the layer number to change.
* @mode: the new wrap mode
*
* Sets the wrap mode for the 'p' coordinate of texture lookups on
* this layer. 'p' is the third coordinate.
*
* Since: 2.0
* Stability: unstable
*/
void
cogl_pipeline_set_layer_wrap_mode_p (CoglPipeline *pipeline,
int layer_index,
CoglPipelineWrapMode mode);
/**
* cogl_pipeline_set_layer_wrap_mode:
* @pipeline: A #CoglPipeline object
* @layer_index: the layer number to change.
* @mode: the new wrap mode
*
* Sets the wrap mode for all three coordinates of texture lookups on
* this layer. This is equivalent to calling
* cogl_pipeline_set_layer_wrap_mode_s(),
* cogl_pipeline_set_layer_wrap_mode_t() and
* cogl_pipeline_set_layer_wrap_mode_p() separately.
*
* Since: 2.0
* Stability: unstable
*/
void
cogl_pipeline_set_layer_wrap_mode (CoglPipeline *pipeline,
int layer_index,
CoglPipelineWrapMode mode);
/**
* cogl_pipeline_add_layer_snippet:
* @pipeline: A #CoglPipeline
* @layer: The layer to hook the snippet to
* @snippet: A #CoglSnippet
*
* Adds a shader snippet that will hook on to the given layer of the
* pipeline. The exact part of the pipeline that the snippet wraps
* around depends on the hook that is given to
* cogl_snippet_new(). Note that some hooks can't be used with a layer
* and need to be added with cogl_pipeline_add_snippet() instead.
*
* Since: 1.10
* Stability: Unstable
*/
void
cogl_pipeline_add_layer_snippet (CoglPipeline *pipeline,
int layer,
CoglSnippet *snippet);
#endif /* COGL_ENABLE_EXPERIMENTAL_API */
COGL_END_DECLS
#endif /* __COGL_PIPELINE_LAYER_STATE_H__ */