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mutter-performance-source/cogl/cogl-pipeline.h
Robert Bragg 8b34a39319 Adds ColorMask support to Cogl
This adds CoglPipeline and CoglFramebuffer support for setting a color
mask which is a bit mask defining which color channels should be written
to the current framebuffer.

The final color mask is the intersection of the framebuffer color mask
and the pipeline color mask. The framebuffer mask affects all rendering
to the framebuffer while the pipeline masks can be used to affect
individual primitives.

Reviewed-by: Neil Roberts <neil@linux.intel.com>
2011-07-19 19:27:09 +01:00

1167 lines
38 KiB
C

/*
* Cogl
*
* An object oriented GL/GLES Abstraction/Utility Layer
*
* Copyright (C) 2007,2008,2009 Intel Corporation.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see <http://www.gnu.org/licenses/>.
*
*
*/
#if !defined(__COGL_H_INSIDE__) && !defined(CLUTTER_COMPILATION)
#error "Only <cogl/cogl.h> can be included directly."
#endif
#ifndef __COGL_PIPELINE_H__
#define __COGL_PIPELINE_H__
G_BEGIN_DECLS
#include <cogl/cogl-types.h>
#include <cogl/cogl-matrix.h>
/**
* SECTION:cogl-pipeline
* @short_description: Functions for creating and manipulating the GPU
* pipeline
*
* Cogl allows creating and manipulating objects representing the full
* configuration of the GPU pipeline. In simplified terms the GPU
* pipeline takes primitive geometry as the input, it first performs
* vertex processing, allowing you to deform your geometry, then
* rasterizes that (turning it from pure geometry into fragments) then
* performs fragment processing including depth testing and texture
* mapping. Finally it blends the result with the framebuffer.
*/
typedef struct _CoglPipeline CoglPipeline;
#define COGL_PIPELINE(OBJECT) ((CoglPipeline *)OBJECT)
/**
* 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_CLAMP_TO_EDGE = 0x812F,
COGL_PIPELINE_WRAP_MODE_AUTOMATIC = 0x0207
} CoglPipelineWrapMode;
/* NB: these values come from the equivalents in gl.h */
/**
* cogl_pipeline_new:
*
* Allocates and initializes a default simple pipeline that will color
* a primitive white.
*
* Return value: a pointer to a new #CoglPipeline
*/
CoglPipeline *
cogl_pipeline_new (void);
/**
* cogl_pipeline_copy:
* @source: a #CoglPipeline object to copy
*
* Creates a new pipeline with the configuration copied from the
* source pipeline.
*
* We would strongly advise developers to always aim to use
* cogl_pipeline_copy() instead of cogl_pipeline_new() whenever there will
* be any similarity between two pipelines. Copying a pipeline helps Cogl
* keep track of a pipelines ancestry which we may use to help minimize GPU
* state changes.
*
* Returns: a pointer to the newly allocated #CoglPipeline
*
* Since: 2.0
*/
CoglPipeline *
cogl_pipeline_copy (CoglPipeline *source);
/**
* cogl_is_pipeline:
* @handle: A CoglHandle
*
* Gets whether the given handle references an existing pipeline object.
*
* Return value: %TRUE if the handle references a #CoglPipeline,
* %FALSE otherwise
*/
gboolean
cogl_is_pipeline (CoglHandle handle);
/**
* cogl_pipeline_set_color:
* @pipeline: A #CoglPipeline object
* @color: The components of the color
*
* Sets the basic color of the pipeline, used when no lighting is enabled.
*
* Note that if you don't add any layers to the pipeline then the color
* will be blended unmodified with the destination; the default blend
* expects premultiplied colors: for example, use (0.5, 0.0, 0.0, 0.5) for
* semi-transparent red. See cogl_color_premultiply().
*
* The default value is (1.0, 1.0, 1.0, 1.0)
*
* Since: 2.0
*/
void
cogl_pipeline_set_color (CoglPipeline *pipeline,
const CoglColor *color);
/**
* cogl_pipeline_set_color4ub:
* @pipeline: A #CoglPipeline object
* @red: The red component
* @green: The green component
* @blue: The blue component
* @alpha: The alpha component
*
* Sets the basic color of the pipeline, used when no lighting is enabled.
*
* The default value is (0xff, 0xff, 0xff, 0xff)
*
* Since: 2.0
*/
void
cogl_pipeline_set_color4ub (CoglPipeline *pipeline,
guint8 red,
guint8 green,
guint8 blue,
guint8 alpha);
/**
* cogl_pipeline_set_color4f:
* @pipeline: A #CoglPipeline object
* @red: The red component
* @green: The green component
* @blue: The blue component
* @alpha: The alpha component
*
* Sets the basic color of the pipeline, used when no lighting is enabled.
*
* The default value is (1.0, 1.0, 1.0, 1.0)
*
* Since: 2.0
*/
void
cogl_pipeline_set_color4f (CoglPipeline *pipeline,
float red,
float green,
float blue,
float alpha);
/**
* cogl_pipeline_get_color:
* @pipeline: A #CoglPipeline object
* @color: (out): The location to store the color
*
* Retrieves the current pipeline color.
*
* Since: 2.0
*/
void
cogl_pipeline_get_color (CoglPipeline *pipeline,
CoglColor *color);
/**
* cogl_pipeline_set_ambient:
* @pipeline: A #CoglPipeline object
* @ambient: The components of the desired ambient color
*
* Sets the pipeline's ambient color, in the standard OpenGL lighting
* model. The ambient color affects the overall color of the object.
*
* Since the diffuse color will be intense when the light hits the surface
* directly, the ambient will be most apparent where the light hits at a
* slant.
*
* The default value is (0.2, 0.2, 0.2, 1.0)
*
* Since: 2.0
*/
void
cogl_pipeline_set_ambient (CoglPipeline *pipeline,
const CoglColor *ambient);
/**
* cogl_pipeline_get_ambient:
* @pipeline: A #CoglPipeline object
* @ambient: The location to store the ambient color
*
* Retrieves the current ambient color for @pipeline
*
* Since: 2.0
*/
void
cogl_pipeline_get_ambient (CoglPipeline *pipeline,
CoglColor *ambient);
/**
* cogl_pipeline_set_diffuse:
* @pipeline: A #CoglPipeline object
* @diffuse: The components of the desired diffuse color
*
* Sets the pipeline's diffuse color, in the standard OpenGL lighting
* model. The diffuse color is most intense where the light hits the
* surface directly - perpendicular to the surface.
*
* The default value is (0.8, 0.8, 0.8, 1.0)
*
* Since: 2.0
*/
void
cogl_pipeline_set_diffuse (CoglPipeline *pipeline,
const CoglColor *diffuse);
/**
* cogl_pipeline_get_diffuse:
* @pipeline: A #CoglPipeline object
* @diffuse: The location to store the diffuse color
*
* Retrieves the current diffuse color for @pipeline
*
* Since: 2.0
*/
void
cogl_pipeline_get_diffuse (CoglPipeline *pipeline,
CoglColor *diffuse);
/**
* cogl_pipeline_set_ambient_and_diffuse:
* @pipeline: A #CoglPipeline object
* @color: The components of the desired ambient and diffuse colors
*
* Conveniently sets the diffuse and ambient color of @pipeline at the same
* time. See cogl_pipeline_set_ambient() and cogl_pipeline_set_diffuse().
*
* The default ambient color is (0.2, 0.2, 0.2, 1.0)
*
* The default diffuse color is (0.8, 0.8, 0.8, 1.0)
*
* Since: 2.0
*/
void
cogl_pipeline_set_ambient_and_diffuse (CoglPipeline *pipeline,
const CoglColor *color);
/**
* cogl_pipeline_set_specular:
* @pipeline: A #CoglPipeline object
* @specular: The components of the desired specular color
*
* Sets the pipeline's specular color, in the standard OpenGL lighting
* model. The intensity of the specular color depends on the viewport
* position, and is brightest along the lines of reflection.
*
* The default value is (0.0, 0.0, 0.0, 1.0)
*
* Since: 2.0
*/
void
cogl_pipeline_set_specular (CoglPipeline *pipeline,
const CoglColor *specular);
/**
* cogl_pipeline_get_specular:
* @pipeline: A #CoglPipeline object
* @specular: The location to store the specular color
*
* Retrieves the pipelines current specular color.
*
* Since: 2.0
*/
void
cogl_pipeline_get_specular (CoglPipeline *pipeline,
CoglColor *specular);
/**
* cogl_pipeline_set_shininess:
* @pipeline: A #CoglPipeline object
* @shininess: The desired shininess; must be >= 0.0
*
* Sets the shininess of the pipeline, in the standard OpenGL lighting
* model, which determines the size of the specular highlights. A
* higher @shininess will produce smaller highlights which makes the
* object appear more shiny.
*
* The default value is 0.0
*
* Since: 2.0
*/
void
cogl_pipeline_set_shininess (CoglPipeline *pipeline,
float shininess);
/**
* cogl_pipeline_get_shininess:
* @pipeline: A #CoglPipeline object
*
* Retrieves the pipelines current emission color.
*
* Return value: The pipelines current shininess value
*
* Since: 2.0
*/
float
cogl_pipeline_get_shininess (CoglPipeline *pipeline);
/**
* cogl_pipeline_set_emission:
* @pipeline: A #CoglPipeline object
* @emission: The components of the desired emissive color
*
* Sets the pipeline's emissive color, in the standard OpenGL lighting
* model. It will look like the surface is a light source emitting this
* color.
*
* The default value is (0.0, 0.0, 0.0, 1.0)
*
* Since: 2.0
*/
void
cogl_pipeline_set_emission (CoglPipeline *pipeline,
const CoglColor *emission);
/**
* cogl_pipeline_get_emission:
* @pipeline: A #CoglPipeline object
* @emission: The location to store the emission color
*
* Retrieves the pipelines current emission color.
*
* Since: 2.0
*/
void
cogl_pipeline_get_emission (CoglPipeline *pipeline,
CoglColor *emission);
/**
* CoglPipelineAlphaFunc:
* @COGL_PIPELINE_ALPHA_FUNC_NEVER: Never let the fragment through.
* @COGL_PIPELINE_ALPHA_FUNC_LESS: Let the fragment through if the incoming
* alpha value is less than the reference alpha value
* @COGL_PIPELINE_ALPHA_FUNC_EQUAL: Let the fragment through if the incoming
* alpha value equals the reference alpha value
* @COGL_PIPELINE_ALPHA_FUNC_LEQUAL: Let the fragment through if the incoming
* alpha value is less than or equal to the reference alpha value
* @COGL_PIPELINE_ALPHA_FUNC_GREATER: Let the fragment through if the incoming
* alpha value is greater than the reference alpha value
* @COGL_PIPELINE_ALPHA_FUNC_NOTEQUAL: Let the fragment through if the incoming
* alpha value does not equal the reference alpha value
* @COGL_PIPELINE_ALPHA_FUNC_GEQUAL: Let the fragment through if the incoming
* alpha value is greater than or equal to the reference alpha value.
* @COGL_PIPELINE_ALPHA_FUNC_ALWAYS: Always let the fragment through.
*
* Alpha testing happens before blending primitives with the framebuffer and
* gives an opportunity to discard fragments based on a comparison with the
* incoming alpha value and a reference alpha value. The #CoglPipelineAlphaFunc
* determines how the comparison is done.
*/
typedef enum {
COGL_PIPELINE_ALPHA_FUNC_NEVER = 0x0200,
COGL_PIPELINE_ALPHA_FUNC_LESS = 0x0201,
COGL_PIPELINE_ALPHA_FUNC_EQUAL = 0x0202,
COGL_PIPELINE_ALPHA_FUNC_LEQUAL = 0x0203,
COGL_PIPELINE_ALPHA_FUNC_GREATER = 0x0204,
COGL_PIPELINE_ALPHA_FUNC_NOTEQUAL = 0x0205,
COGL_PIPELINE_ALPHA_FUNC_GEQUAL = 0x0206,
COGL_PIPELINE_ALPHA_FUNC_ALWAYS = 0x0207
} CoglPipelineAlphaFunc;
/* NB: these values come from the equivalents in gl.h */
/**
* cogl_pipeline_set_alpha_test_function:
* @pipeline: A #CoglPipeline object
* @alpha_func: A @CoglPipelineAlphaFunc constant
* @alpha_reference: A reference point that the chosen alpha function uses
* to compare incoming fragments to.
*
* Before a primitive is blended with the framebuffer, it goes through an
* alpha test stage which lets you discard fragments based on the current
* alpha value. This function lets you change the function used to evaluate
* the alpha channel, and thus determine which fragments are discarded
* and which continue on to the blending stage.
*
* The default is %COGL_PIPELINE_ALPHA_FUNC_ALWAYS
*
* Since: 2.0
*/
void
cogl_pipeline_set_alpha_test_function (CoglPipeline *pipeline,
CoglPipelineAlphaFunc alpha_func,
float alpha_reference);
/**
* cogl_pipeline_get_alpha_test_function:
* @pipeline: A #CoglPipeline object
*
* Return value: The alpha test function of @pipeline.
*
* Since: 2.0
*/
CoglPipelineAlphaFunc
cogl_pipeline_get_alpha_test_function (CoglPipeline *pipeline);
/**
* cogl_pipeline_get_alpha_test_reference:
* @pipeline: A #CoglPipeline object
*
* Return value: The alpha test reference value of @pipeline.
*
* Since: 2.0
*/
float
cogl_pipeline_get_alpha_test_reference (CoglPipeline *pipeline);
/**
* cogl_pipeline_set_blend:
* @pipeline: A #CoglPipeline object
* @blend_string: A <link linkend="cogl-Blend-Strings">Cogl blend string</link>
* describing the desired blend function.
* @error: return location for a #GError that may report lack of driver
* support if you give separate blend string statements for the alpha
* channel and RGB channels since some drivers, or backends such as
* GLES 1.1, don't support this feature. May be %NULL, in which case a
* warning will be printed out using GLib's logging facilities if an
* error is encountered.
*
* If not already familiar; please refer <link linkend="cogl-Blend-Strings">here</link>
* for an overview of what blend strings are, and their syntax.
*
* Blending occurs after the alpha test function, and combines fragments with
* the framebuffer.
* Currently the only blend function Cogl exposes is ADD(). So any valid
* blend statements will be of the form:
*
* |[
* &lt;channel-mask&gt;=ADD(SRC_COLOR*(&lt;factor&gt;), DST_COLOR*(&lt;factor&gt;))
* ]|
*
* <warning>The brackets around blend factors are currently not
* optional!</warning>
*
* This is the list of source-names usable as blend factors:
* <itemizedlist>
* <listitem><para>SRC_COLOR: The color of the in comming fragment</para></listitem>
* <listitem><para>DST_COLOR: The color of the framebuffer</para></listitem>
* <listitem><para>CONSTANT: The constant set via cogl_pipeline_set_blend_constant()</para></listitem>
* </itemizedlist>
*
* The source names can be used according to the
* <link linkend="cogl-Blend-String-syntax">color-source and factor syntax</link>,
* so for example "(1-SRC_COLOR[A])" would be a valid factor, as would
* "(CONSTANT[RGB])"
*
* These can also be used as factors:
* <itemizedlist>
* <listitem>0: (0, 0, 0, 0)</listitem>
* <listitem>1: (1, 1, 1, 1)</listitem>
* <listitem>SRC_ALPHA_SATURATE_FACTOR: (f,f,f,1) where f = MIN(SRC_COLOR[A],1-DST_COLOR[A])</listitem>
* </itemizedlist>
*
* <note>Remember; all color components are normalized to the range [0, 1]
* before computing the result of blending.</note>
*
* <example id="cogl-Blend-Strings-blend-unpremul">
* <title>Blend Strings/1</title>
* <para>Blend a non-premultiplied source over a destination with
* premultiplied alpha:</para>
* <programlisting>
* "RGB = ADD(SRC_COLOR*(SRC_COLOR[A]), DST_COLOR*(1-SRC_COLOR[A]))"
* "A = ADD(SRC_COLOR, DST_COLOR*(1-SRC_COLOR[A]))"
* </programlisting>
* </example>
*
* <example id="cogl-Blend-Strings-blend-premul">
* <title>Blend Strings/2</title>
* <para>Blend a premultiplied source over a destination with
* premultiplied alpha</para>
* <programlisting>
* "RGBA = ADD(SRC_COLOR, DST_COLOR*(1-SRC_COLOR[A]))"
* </programlisting>
* </example>
*
* The default blend string is:
* |[
* RGBA = ADD (SRC_COLOR, DST_COLOR*(1-SRC_COLOR[A]))
* ]|
*
* That gives normal alpha-blending when the calculated color for the pipeline
* is in premultiplied form.
*
* Return value: %TRUE if the blend string was successfully parsed, and the
* described blending is supported by the underlying driver/hardware. If
* there was an error, %FALSE is returned and @error is set accordingly (if
* present).
*
* Since: 2.0
*/
gboolean
cogl_pipeline_set_blend (CoglPipeline *pipeline,
const char *blend_string,
GError **error);
/**
* cogl_pipeline_set_blend_constant:
* @pipeline: A #CoglPipeline object
* @constant_color: The constant color you want
*
* When blending is setup to reference a CONSTANT blend factor then
* blending will depend on the constant set with this function.
*
* Since: 2.0
*/
void
cogl_pipeline_set_blend_constant (CoglPipeline *pipeline,
const CoglColor *constant_color);
/**
* cogl_pipeline_set_point_size:
* @pipeline: a #CoglHandle to a pipeline.
* @point_size: the new point size.
*
* Changes the size of points drawn when %COGL_VERTICES_MODE_POINTS is
* used with the vertex buffer API. Note that typically the GPU will
* only support a limited minimum and maximum range of point sizes. If
* the chosen point size is outside that range then the nearest value
* within that range will be used instead. The size of a point is in
* screen space so it will be the same regardless of any
* transformations. The default point size is 1.0.
*
* Since: 2.0
*/
void
cogl_pipeline_set_point_size (CoglHandle pipeline,
float point_size);
/**
* cogl_pipeline_get_point_size:
* @pipeline: a #CoglHandle to a pipeline.
*
* Get the size of points drawn when %COGL_VERTICES_MODE_POINTS is
* used with the vertex buffer API.
*
* Return value: the point size of the pipeline.
*
* Since: 2.0
*/
float
cogl_pipeline_get_point_size (CoglHandle pipeline);
#define cogl_pipeline_get_color_mask cogl_pipeline_get_color_mask_EXP
/**
* cogl_pipeline_get_color_mask:
* @pipeline: a #CoglPipeline object.
*
* Gets the current #CoglColorMask of which channels would be written to the
* current framebuffer. Each bit set in the mask means that the
* corresponding color would be written.
*
* Returns: A #CoglColorMask
* Since: 1.8
* Stability: unstable
*/
CoglColorMask
cogl_pipeline_get_color_mask (CoglPipeline *pipeline);
#define cogl_pipeline_set_color_mask cogl_pipeline_set_color_mask_EXP
/**
* cogl_pipeline_set_color_mask:
* @pipeline: a #CoglPipeline object.
* @color_mask: A #CoglColorMask of which color channels to write to
* the current framebuffer.
*
* Defines a bit mask of which color channels should be written to the
* current framebuffer. If a bit is set in @color_mask that means that
* color will be written.
*
* Since: 1.8
* Stability: unstable
*/
void
cogl_pipeline_set_color_mask (CoglPipeline *pipeline,
CoglColorMask color_mask);
/**
* cogl_pipeline_get_user_program:
* @pipeline: a #CoglPipeline object.
*
* Queries what user program has been associated with the given
* @pipeline using cogl_pipeline_set_user_program().
*
* Return value: The current user program or %COGL_INVALID_HANDLE.
*
* Since: 2.0
*/
CoglHandle
cogl_pipeline_get_user_program (CoglPipeline *pipeline);
/**
* cogl_pipeline_set_user_program:
* @pipeline: a #CoglPipeline object.
* @program: A #CoglHandle to a linked CoglProgram
*
* Associates a linked CoglProgram with the given pipeline so that the
* program can take full control of vertex and/or fragment processing.
*
* This is an example of how it can be used to associate an ARBfp
* program with a #CoglPipeline:
* |[
* CoglHandle shader;
* CoglHandle program;
* CoglPipeline *pipeline;
*
* shader = cogl_create_shader (COGL_SHADER_TYPE_FRAGMENT);
* cogl_shader_source (shader,
* "!!ARBfp1.0\n"
* "MOV result.color,fragment.color;\n"
* "END\n");
* cogl_shader_compile (shader);
*
* program = cogl_create_program ();
* cogl_program_attach_shader (program, shader);
* cogl_program_link (program);
*
* pipeline = cogl_pipeline_new ();
* cogl_pipeline_set_user_program (pipeline, program);
*
* cogl_set_source_color4ub (0xff, 0x00, 0x00, 0xff);
* cogl_rectangle (0, 0, 100, 100);
* ]|
*
* It is possibly worth keeping in mind that this API is not part of
* the long term design for how we want to expose shaders to Cogl
* developers (We are planning on deprecating the cogl_program and
* cogl_shader APIs in favour of a "snippet" framework) but in the
* meantime we hope this will handle most practical GLSL and ARBfp
* requirements.
*
* Also remember you need to check for either the
* %COGL_FEATURE_SHADERS_GLSL or %COGL_FEATURE_SHADERS_ARBFP before
* using the cogl_program or cogl_shader API.
*
* Since: 2.0
*/
void
cogl_pipeline_set_user_program (CoglPipeline *pipeline,
CoglHandle program);
/**
* cogl_pipeline_set_layer:
* @pipeline: A #CoglPipeline object
* @layer_index: the index of the layer
* @texture: a #CoglHandle 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.
*
* <note>In the future, we may define other types of pipeline layers, such
* as purely GLSL based layers.</note>
*
* Since: 2.0
*/
void
cogl_pipeline_set_layer_texture (CoglPipeline *pipeline,
int layer_index,
CoglHandle texture);
/**
* 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
*/
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 #GError 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_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_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
*/
gboolean
cogl_pipeline_set_layer_combine (CoglPipeline *pipeline,
int layer_index,
const char *blend_string,
GError **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
*/
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.
*/
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
*/
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%.
*/
void
cogl_pipeline_set_layer_filters (CoglPipeline *pipeline,
int layer_index,
CoglPipelineFilter min_filter,
CoglPipelineFilter mag_filter);
/**
* cogl_pipeline_set_layer_point_sprite_coords_enabled:
* @pipeline: a #CoglHandle to a pipeline.
* @layer_index: the layer number to change.
* @enable: whether to enable point sprite coord generation.
* @error: A return location for a GError, 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_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
*/
gboolean
cogl_pipeline_set_layer_point_sprite_coords_enabled (CoglPipeline *pipeline,
int layer_index,
gboolean enable,
GError **error);
/**
* cogl_pipeline_get_layer_point_sprite_coords_enabled:
* @pipeline: a #CoglHandle to a pipeline.
* @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
*/
gboolean
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
*/
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
*/
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
*/
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
*/
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
*/
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
*/
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
*/
void
cogl_pipeline_set_layer_wrap_mode (CoglPipeline *pipeline,
int layer_index,
CoglPipelineWrapMode mode);
#ifdef COGL_ENABLE_EXPERIMENTAL_API
/**
* cogl_pipeline_set_depth_state:
* @pipeline: A #CoglPipeline object
* @state: A #CoglDepthState struct
* @error: A #GError to report failures to setup the given @state.
*
* This commits all the depth state configured in @state struct to the
* given @pipeline. The configuration values are copied into the
* pipeline so there is no requirement to keep the #CoglDepthState
* struct around if you don't need it any more.
*
* Note: Since some platforms do not support the depth range feature
* it is possible for this function to fail and report an @error.
*
* Returns: TRUE if the GPU supports all the given @state else %FALSE
* and returns an @error.
*
* Since: 2.0
* Stability: Unstable
*/
gboolean
cogl_pipeline_set_depth_state (CoglPipeline *pipeline,
const CoglDepthState *state,
GError **error);
/**
* cogl_pipeline_get_depth_state
* @pipeline: A #CoglPipeline object
* @state: A destination #CoglDepthState struct
*
* Retrieves the current depth state configuration for the given
* @pipeline as previously set using cogl_pipeline_set_depth_state().
*
* Since: 2.0
* Stability: Unstable
*/
void
cogl_pipeline_get_depth_state (CoglPipeline *pipeline,
CoglDepthState *state_out);
/**
* CoglPipelineLayerCallback:
* @pipeline: The #CoglPipeline whos layers are being iterated
* @layer_index: The current layer index
* @user_data: The private data passed to cogl_pipeline_foreach_layer()
*
* The callback prototype used with cogl_pipeline_foreach_layer() for
* iterating all the layers of a @pipeline.
*
* Since: 2.0
* Stability: Unstable
*/
typedef gboolean (*CoglPipelineLayerCallback) (CoglPipeline *pipeline,
int layer_index,
void *user_data);
/**
* cogl_pipeline_foreach_layer:
* @pipeline: A #CoglPipeline object
* @callback: A #CoglPipelineLayerCallback to be called for each layer
* index
* @user_data: Private data that will be passed to the callback
*
* Iterates all the layer indices of the given @pipeline.
*
* Since: 2.0
* Stability: Unstable
*/
void
cogl_pipeline_foreach_layer (CoglPipeline *pipeline,
CoglPipelineLayerCallback callback,
void *user_data);
#endif /* COGL_ENABLE_EXPERIMENTAL_API */
G_END_DECLS
#endif /* __COGL_PIPELINE_H__ */