/*
* 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(COGL_COMPILATION)
#error "Only <cogl/cogl.h> can be included directly."
#endif
#ifndef __COGL_MATERIAL_H__
#define __COGL_MATERIAL_H__
#include <cogl/cogl-types.h>
#include <cogl/cogl-matrix.h>
#include <cogl/cogl-depth-state.h>
G_BEGIN_DECLS
/**
* SECTION:cogl-material
* @short_description: Fuctions for creating and manipulating materials
*
* COGL allows creating and manipulating materials used to fill in
* geometry. Materials may simply be lighting attributes (such as an
* ambient and diffuse colour) or might represent one or more textures
* blended together.
*/
typedef struct _CoglMaterial CoglMaterial;
typedef struct _CoglMaterialLayer CoglMaterialLayer;
#define COGL_MATERIAL(OBJECT) ((CoglMaterial *)OBJECT)
/**
* CoglMaterialFilter:
* @COGL_MATERIAL_FILTER_NEAREST: Measuring in manhatten distance from the,
* current pixel center, use the nearest texture texel
* @COGL_MATERIAL_FILTER_LINEAR: Use the weighted average of the 4 texels
* nearest the current pixel center
* @COGL_MATERIAL_FILTER_NEAREST_MIPMAP_NEAREST: Select the mimap level whose
* texel size most closely matches the current pixel, and use the
* %COGL_MATERIAL_FILTER_NEAREST criterion
* @COGL_MATERIAL_FILTER_LINEAR_MIPMAP_NEAREST: Select the mimap level whose
* texel size most closely matches the current pixel, and use the
* %COGL_MATERIAL_FILTER_LINEAR criterion
* @COGL_MATERIAL_FILTER_NEAREST_MIPMAP_LINEAR: Select the two mimap levels
* whose texel size most closely matches the current pixel, use
* the %COGL_MATERIAL_FILTER_NEAREST criterion on each one and take
* their weighted average
* @COGL_MATERIAL_FILTER_LINEAR_MIPMAP_LINEAR: Select the two mimap levels
* whose texel size most closely matches the current pixel, use
* the %COGL_MATERIAL_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_MATERIAL_FILTER_NEAREST = 0x2600,
COGL_MATERIAL_FILTER_LINEAR = 0x2601,
COGL_MATERIAL_FILTER_NEAREST_MIPMAP_NEAREST = 0x2700,
COGL_MATERIAL_FILTER_LINEAR_MIPMAP_NEAREST = 0x2701,
COGL_MATERIAL_FILTER_NEAREST_MIPMAP_LINEAR = 0x2702,
COGL_MATERIAL_FILTER_LINEAR_MIPMAP_LINEAR = 0x2703
} CoglMaterialFilter;
/* NB: these values come from the equivalents in gl.h */
/**
* CoglMaterialWrapMode:
* @COGL_MATERIAL_WRAP_MODE_REPEAT: The texture will be repeated. This
* is useful for example to draw a tiled background.
* @COGL_MATERIAL_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_MATERIAL_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_MATERIAL_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: 1.4
*/
/* 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 CoglMaterialWrapModeInternal
* enum so no conversion is actually needed.
*/
typedef enum {
COGL_MATERIAL_WRAP_MODE_REPEAT = 0x2901,
COGL_MATERIAL_WRAP_MODE_CLAMP_TO_EDGE = 0x812F,
COGL_MATERIAL_WRAP_MODE_AUTOMATIC = 0x0207
} CoglMaterialWrapMode;
/* NB: these values come from the equivalents in gl.h */
/**
* cogl_material_new:
*
* Allocates and initializes a blank white material
*
* Return value: a pointer to a new #CoglMaterial
*/
CoglMaterial *
cogl_material_new (void);
/**
* cogl_material_copy:
* @source: a #CoglMaterial object to copy
*
* Creates a new material with the configuration copied from the
* source material.
*
* We would strongly advise developers to always aim to use
* cogl_material_copy() instead of cogl_material_new() whenever there will
* be any similarity between two materials. Copying a material helps Cogl
* keep track of a materials ancestry which we may use to help minimize GPU
* state changes.
*
* Returns: a pointer to the newly allocated #CoglMaterial
*
* Since: 1.2
*/
CoglMaterial *
cogl_material_copy (CoglMaterial *source);
#ifndef COGL_DISABLE_DEPRECATED
/**
* cogl_material_ref:
* @material: a #CoglMaterial object.
*
* Increment the reference count for a #CoglMaterial.
*
* Return value: the @material.
*
* Since: 1.0
*
* Deprecated: 1.2: Use cogl_object_ref() instead
*/
CoglHandle
cogl_material_ref (CoglHandle material) G_GNUC_DEPRECATED;
/**
* cogl_material_unref:
* @material: a #CoglMaterial object.
*
* Decrement the reference count for a #CoglMaterial.
*
* Since: 1.0
*
* Deprecated: 1.2: Use cogl_object_unref() instead
*/
void
cogl_material_unref (CoglHandle material) G_GNUC_DEPRECATED;
#endif /* COGL_DISABLE_DEPRECATED */
/**
* cogl_is_material:
* @handle: A CoglHandle
*
* Gets whether the given handle references an existing material object.
*
* Return value: %TRUE if the handle references a #CoglMaterial,
* %FALSE otherwise
*/
CoglBool
cogl_is_material (CoglHandle handle);
/**
* cogl_material_set_color:
* @material: A #CoglMaterial object
* @color: The components of the color
*
* Sets the basic color of the material, used when no lighting is enabled.
*
* Note that if you don't add any layers to the material 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: 1.0
*/
void
cogl_material_set_color (CoglMaterial *material,
const CoglColor *color);
/**
* cogl_material_set_color4ub:
* @material: A #CoglMaterial object
* @red: The red component
* @green: The green component
* @blue: The blue component
* @alpha: The alpha component
*
* Sets the basic color of the material, used when no lighting is enabled.
*
* The default value is (0xff, 0xff, 0xff, 0xff)
*
* Since: 1.0
*/
void
cogl_material_set_color4ub (CoglMaterial *material,
uint8_t red,
uint8_t green,
uint8_t blue,
uint8_t alpha);
/**
* cogl_material_set_color4f:
* @material: A #CoglMaterial object
* @red: The red component
* @green: The green component
* @blue: The blue component
* @alpha: The alpha component
*
* Sets the basic color of the material, used when no lighting is enabled.
*
* The default value is (1.0, 1.0, 1.0, 1.0)
*
* Since: 1.0
*/
void
cogl_material_set_color4f (CoglMaterial *material,
float red,
float green,
float blue,
float alpha);
/**
* cogl_material_get_color:
* @material: A #CoglMaterial object
* @color: (out): The location to store the color
*
* Retrieves the current material color.
*
* Since: 1.0
*/
void
cogl_material_get_color (CoglMaterial *material,
CoglColor *color);
/**
* cogl_material_set_ambient:
* @material: A #CoglMaterial object
* @ambient: The components of the desired ambient color
*
* Sets the material'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: 1.0
*/
void
cogl_material_set_ambient (CoglMaterial *material,
const CoglColor *ambient);
/**
* cogl_material_get_ambient:
* @material: A #CoglMaterial object
* @ambient: The location to store the ambient color
*
* Retrieves the current ambient color for @material
*
* Since: 1.0
*/
void
cogl_material_get_ambient (CoglMaterial *material,
CoglColor *ambient);
/**
* cogl_material_set_diffuse:
* @material: A #CoglMaterial object
* @diffuse: The components of the desired diffuse color
*
* Sets the material'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: 1.0
*/
void
cogl_material_set_diffuse (CoglMaterial *material,
const CoglColor *diffuse);
/**
* cogl_material_get_diffuse:
* @material: A #CoglMaterial object
* @diffuse: The location to store the diffuse color
*
* Retrieves the current diffuse color for @material
*
* Since: 1.0
*/
void
cogl_material_get_diffuse (CoglMaterial *material,
CoglColor *diffuse);
/**
* cogl_material_set_ambient_and_diffuse:
* @material: A #CoglMaterial object
* @color: The components of the desired ambient and diffuse colors
*
* Conveniently sets the diffuse and ambient color of @material at the same
* time. See cogl_material_set_ambient() and cogl_material_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: 1.0
*/
void
cogl_material_set_ambient_and_diffuse (CoglMaterial *material,
const CoglColor *color);
/**
* cogl_material_set_specular:
* @material: A #CoglMaterial object
* @specular: The components of the desired specular color
*
* Sets the material'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: 1.0
*/
void
cogl_material_set_specular (CoglMaterial *material,
const CoglColor *specular);
/**
* cogl_material_get_specular:
* @material: A #CoglMaterial object
* @specular: The location to store the specular color
*
* Retrieves the materials current specular color.
*
* Since: 1.0
*/
void
cogl_material_get_specular (CoglMaterial *material,
CoglColor *specular);
/**
* cogl_material_set_shininess:
* @material: A #CoglMaterial object
* @shininess: The desired shininess; must be >= 0.0
*
* Sets the shininess of the material, 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: 1.0
*/
void
cogl_material_set_shininess (CoglMaterial *material,
float shininess);
/**
* cogl_material_get_shininess:
* @material: A #CoglMaterial object
*
* Retrieves the materials current emission color.
*
* Return value: The materials current shininess value
*
* Since: 1.0
*/
float
cogl_material_get_shininess (CoglMaterial *material);
/**
* cogl_material_set_emission:
* @material: A #CoglMaterial object
* @emission: The components of the desired emissive color
*
* Sets the material'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: 1.0
*/
void
cogl_material_set_emission (CoglMaterial *material,
const CoglColor *emission);
/**
* cogl_material_get_emission:
* @material: A #CoglMaterial object
* @emission: The location to store the emission color
*
* Retrieves the materials current emission color.
*
* Since: 1.0
*/
void
cogl_material_get_emission (CoglMaterial *material,
CoglColor *emission);
/**
* CoglMaterialAlphaFunc:
* @COGL_MATERIAL_ALPHA_FUNC_NEVER: Never let the fragment through.
* @COGL_MATERIAL_ALPHA_FUNC_LESS: Let the fragment through if the incoming
* alpha value is less than the reference alpha value
* @COGL_MATERIAL_ALPHA_FUNC_EQUAL: Let the fragment through if the incoming
* alpha value equals the reference alpha value
* @COGL_MATERIAL_ALPHA_FUNC_LEQUAL: Let the fragment through if the incoming
* alpha value is less than or equal to the reference alpha value
* @COGL_MATERIAL_ALPHA_FUNC_GREATER: Let the fragment through if the incoming
* alpha value is greater than the reference alpha value
* @COGL_MATERIAL_ALPHA_FUNC_NOTEQUAL: Let the fragment through if the incoming
* alpha value does not equal the reference alpha value
* @COGL_MATERIAL_ALPHA_FUNC_GEQUAL: Let the fragment through if the incoming
* alpha value is greater than or equal to the reference alpha value.
* @COGL_MATERIAL_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 #CoglMaterialAlphaFunc
* determines how the comparison is done.
*/
typedef enum {
COGL_MATERIAL_ALPHA_FUNC_NEVER = 0x0200,
COGL_MATERIAL_ALPHA_FUNC_LESS = 0x0201,
COGL_MATERIAL_ALPHA_FUNC_EQUAL = 0x0202,
COGL_MATERIAL_ALPHA_FUNC_LEQUAL = 0x0203,
COGL_MATERIAL_ALPHA_FUNC_GREATER = 0x0204,
COGL_MATERIAL_ALPHA_FUNC_NOTEQUAL = 0x0205,
COGL_MATERIAL_ALPHA_FUNC_GEQUAL = 0x0206,
COGL_MATERIAL_ALPHA_FUNC_ALWAYS = 0x0207
} CoglMaterialAlphaFunc;
/**
* cogl_material_set_alpha_test_function:
* @material: A #CoglMaterial object
* @alpha_func: A @CoglMaterialAlphaFunc 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_MATERIAL_ALPHA_FUNC_ALWAYS
*
* Since: 1.0
*/
void
cogl_material_set_alpha_test_function (CoglMaterial *material,
CoglMaterialAlphaFunc alpha_func,
float alpha_reference);
/**
* cogl_material_set_blend:
* @material: A #CoglMaterial 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:
*
* |[
* <channel-mask>=ADD(SRC_COLOR*(<factor>), DST_COLOR*(<factor>))
* ]|
*
* <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_material_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 material
* 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: 1.0
*/
CoglBool
cogl_material_set_blend (CoglMaterial *material,
const char *blend_string,
GError **error);
/**
* cogl_material_set_blend_constant:
* @material: A #CoglMaterial 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: 1.0
*/
void
cogl_material_set_blend_constant (CoglMaterial *material,
const CoglColor *constant_color);
/**
* cogl_material_set_point_size:
* @material: a material.
* @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: 1.4
*/
void
cogl_material_set_point_size (CoglMaterial *material,
float point_size);
/**
* cogl_material_get_point_size:
* @material: a #CoglHandle to a material.
*
* 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 material.
*
* Since: 1.4
*/
float
cogl_material_get_point_size (CoglMaterial *material);
/**
* cogl_material_get_user_program:
* @material: a #CoglMaterial object.
*
* Queries what user program has been associated with the given
* @material using cogl_material_set_user_program().
*
* Return value: (transfer none): The current user program
* or %COGL_INVALID_HANDLE.
*
* Since: 1.4
*/
CoglHandle
cogl_material_get_user_program (CoglMaterial *material);
/**
* cogl_material_set_user_program:
* @material: a #CoglMaterial object.
* @program: A #CoglHandle to a linked CoglProgram
*
* Associates a linked CoglProgram with the given material 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 #CoglMaterial:
* |[
* CoglHandle shader;
* CoglHandle program;
* CoglMaterial *material;
*
* 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);
*
* material = cogl_material_new ();
* cogl_material_set_user_program (material, 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: 1.4
*/
void
cogl_material_set_user_program (CoglMaterial *material,
CoglHandle program);
/**
* cogl_material_set_layer:
* @material: A #CoglMaterial 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 material 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 material layers, such
* as purely GLSL based layers.</note>
*
* Since: 1.0
*/
void
cogl_material_set_layer (CoglMaterial *material,
int layer_index,
CoglHandle texture);
/**
* cogl_material_remove_layer:
* @material: A #CoglMaterial object
* @layer_index: Specifies the layer you want to remove
*
* This function removes a layer from your material
*/
void
cogl_material_remove_layer (CoglMaterial *material,
int layer_index);
/**
* cogl_material_set_layer_combine:
* @material: A #CoglMaterial 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_material_set_layer_constant()</listitem>
* </varlistentry>
* <varlistentry>
* <term>PRIMARY</term>
* <listitem>Use the color of the material as set with
* cogl_material_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 material as set with
* cogl_material_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_material_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: 1.0
*/
CoglBool
cogl_material_set_layer_combine (CoglMaterial *material,
int layer_index,
const char *blend_string,
GError **error);
/**
* cogl_material_set_layer_combine_constant:
* @material: A #CoglMaterial 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: 1.0
*/
void
cogl_material_set_layer_combine_constant (CoglMaterial *material,
int layer_index,
const CoglColor *constant);
/**
* cogl_material_set_layer_matrix:
* @material: A #CoglMaterial object
* @layer_index: the index for the layer inside @material
* @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 material used to fill your geometry.
*/
void
cogl_material_set_layer_matrix (CoglMaterial *material,
int layer_index,
const CoglMatrix *matrix);
/**
* cogl_material_get_layers:
* @material: A #CoglMaterial object
*
* This function lets you access a material's internal list of layers
* for iteration.
*
* <note>You should avoid using this API if possible since it was only
* made public by mistake and will be deprecated when we have
* suitable alternative.</note>
*
* <note>It's important to understand that the list returned may not
* remain valid if you modify the material or any of the layers in any
* way and so you would have to re-get the list in that
* situation.</note>
*
* Return value: (element-type CoglMaterialLayer) (transfer none): A
* list of #CoglMaterialLayer<!-- -->'s that can be passed to the
* cogl_material_layer_* functions. The list is owned by Cogl and it
* should not be modified or freed
*/
const GList *
cogl_material_get_layers (CoglMaterial *material);
/**
* cogl_material_get_n_layers:
* @material: A #CoglMaterial object
*
* Retrieves the number of layers defined for the given @material
*
* Return value: the number of layers
*
* Since: 1.0
*/
int
cogl_material_get_n_layers (CoglMaterial *material);
/**
* CoglMaterialLayerType:
* @COGL_MATERIAL_LAYER_TYPE_TEXTURE: The layer represents a
* <link linkend="cogl-Textures">texture</link>
*
* Available types of layers for a #CoglMaterial. This enumeration
* might be expanded in later versions.
*
* Since: 1.0
*/
typedef enum {
COGL_MATERIAL_LAYER_TYPE_TEXTURE
} CoglMaterialLayerType;
/**
* cogl_material_layer_get_type:
* @layer: A #CoglMaterialLayer object
*
* Retrieves the type of the layer
*
* Currently there is only one type of layer defined:
* %COGL_MATERIAL_LAYER_TYPE_TEXTURE, but considering we may add purely GLSL
* based layers in the future, you should write code that checks the type
* first.
*
* Return value: the type of the layer
*/
CoglMaterialLayerType
cogl_material_layer_get_type (CoglMaterialLayer *layer);
/**
* cogl_material_layer_get_texture:
* @layer: A #CoglMaterialLayer object
*
* Extracts a texture handle for a specific layer.
*
* <note>In the future Cogl may support purely GLSL based layers; for those
* layers this function which will likely return %COGL_INVALID_HANDLE if you
* try to get the texture handle from them. Considering this scenario, you
* should call cogl_material_layer_get_type() first in order check it is of
* type %COGL_MATERIAL_LAYER_TYPE_TEXTURE before calling this function.</note>
*
* Return value: (transfer none): a #CoglHandle for the texture inside the layer
*/
CoglHandle
cogl_material_layer_get_texture (CoglMaterialLayer *layer);
/**
* cogl_material_layer_get_min_filter:
* @layer: a #CoglHandle for a material layer
*
* Queries the currently set downscaling filter for a material layer
*
* Return value: the current downscaling filter
*/
CoglMaterialFilter
cogl_material_layer_get_min_filter (CoglMaterialLayer *layer);
/**
* cogl_material_layer_get_mag_filter:
* @layer: A #CoglMaterialLayer object
*
* Queries the currently set downscaling filter for a material later
*
* Return value: the current downscaling filter
*/
CoglMaterialFilter
cogl_material_layer_get_mag_filter (CoglMaterialLayer *layer);
/**
* cogl_material_set_layer_filters:
* @material: A #CoglMaterial 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_material_set_layer_filters (CoglMaterial *material,
int layer_index,
CoglMaterialFilter min_filter,
CoglMaterialFilter mag_filter);
/**
* cogl_material_set_layer_point_sprite_coords_enabled:
* @material: a #CoglHandle to a material.
* @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: 1.4
*/
CoglBool
cogl_material_set_layer_point_sprite_coords_enabled (CoglMaterial *material,
int layer_index,
CoglBool enable,
GError **error);
/**
* cogl_material_get_layer_point_sprite_coords_enabled:
* @material: a #CoglHandle to a material.
* @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: 1.4
*/
CoglBool
cogl_material_get_layer_point_sprite_coords_enabled (CoglMaterial *material,
int layer_index);
/**
* cogl_material_get_layer_wrap_mode_s:
* @material: A #CoglMaterial 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
*/
CoglMaterialWrapMode
cogl_material_get_layer_wrap_mode_s (CoglMaterial *material,
int layer_index);
/**
* cogl_material_set_layer_wrap_mode_s:
* @material: A #CoglMaterial 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: 1.4
*/
void
cogl_material_set_layer_wrap_mode_s (CoglMaterial *material,
int layer_index,
CoglMaterialWrapMode mode);
/**
* cogl_material_get_layer_wrap_mode_t:
* @material: A #CoglMaterial 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
*/
CoglMaterialWrapMode
cogl_material_get_layer_wrap_mode_t (CoglMaterial *material,
int layer_index);
/**
* cogl_material_set_layer_wrap_mode_t:
* @material: A #CoglMaterial 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: 1.4
*/
void
cogl_material_set_layer_wrap_mode_t (CoglMaterial *material,
int layer_index,
CoglMaterialWrapMode mode);
/**
* cogl_material_get_layer_wrap_mode_p:
* @material: A #CoglMaterial 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
*/
CoglMaterialWrapMode
cogl_material_get_layer_wrap_mode_p (CoglMaterial *material,
int layer_index);
/**
* cogl_material_set_layer_wrap_mode_p:
* @material: A #CoglMaterial 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: 1.4
*/
void
cogl_material_set_layer_wrap_mode_p (CoglMaterial *material,
int layer_index,
CoglMaterialWrapMode mode);
/**
* cogl_material_set_layer_wrap_mode:
* @material: A #CoglMaterial 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_material_set_layer_wrap_mode_s(),
* cogl_material_set_layer_wrap_mode_t() and
* cogl_material_set_layer_wrap_mode_p() separately.
*
* Since: 1.4
*/
void
cogl_material_set_layer_wrap_mode (CoglMaterial *material,
int layer_index,
CoglMaterialWrapMode mode);
/**
* cogl_material_layer_get_wrap_mode_s:
* @layer: A #CoglMaterialLayer object
*
* Gets the wrap mode for the 's' coordinate of texture lookups on this layer.
*
* Return value: the wrap mode value for the s coordinate.
*
* Since: 1.4
*/
CoglMaterialWrapMode
cogl_material_layer_get_wrap_mode_s (CoglMaterialLayer *layer);
/**
* cogl_material_layer_get_wrap_mode_t:
* @layer: A #CoglMaterialLayer object
*
* Gets the wrap mode for the 't' coordinate of texture lookups on this layer.
*
* Return value: the wrap mode value for the t coordinate.
*
* Since: 1.4
*/
CoglMaterialWrapMode
cogl_material_layer_get_wrap_mode_t (CoglMaterialLayer *layer);
/**
* cogl_material_layer_get_wrap_mode_p:
* @layer: A #CoglMaterialLayer object
*
* Gets the wrap mode for the 'p' coordinate of texture lookups on
* this layer. 'p' is the third coordinate.
*
* Return value: the wrap mode value for the p coordinate.
*
* Since: 1.4
*/
CoglMaterialWrapMode
cogl_material_layer_get_wrap_mode_p (CoglMaterialLayer *layer);
#ifdef COGL_ENABLE_EXPERIMENTAL_API
/**
* cogl_material_set_depth_state:
* @material: A #CoglMaterial 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 @material. The configuration values are copied into the
* material 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: 1.8
* Stability: Unstable
*/
CoglBool
cogl_material_set_depth_state (CoglMaterial *material,
const CoglDepthState *state,
GError **error);
/**
* cogl_material_get_depth_state:
* @material: A #CoglMaterial object
* @state_out: 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_material_get_depth_state (CoglMaterial *material,
CoglDepthState *state_out);
/**
* CoglMaterialLayerCallback:
* @material: The #CoglMaterial whos layers are being iterated
* @layer_index: The current layer index
* @user_data: The private data passed to cogl_material_foreach_layer()
*
* The callback prototype used with cogl_material_foreach_layer() for
* iterating all the layers of a @material.
*
* Since: 1.4
* Stability: Unstable
*/
typedef CoglBool (*CoglMaterialLayerCallback) (CoglMaterial *material,
int layer_index,
void *user_data);
/**
* cogl_material_foreach_layer:
* @material: A #CoglMaterial object
* @callback: A #CoglMaterialLayerCallback 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 @material.
*
* Since: 1.4
* Stability: Unstable
*/
void
cogl_material_foreach_layer (CoglMaterial *material,
CoglMaterialLayerCallback callback,
void *user_data);
#endif /* COGL_ENABLE_EXPERIMENTAL_API */
G_END_DECLS
#endif /* __COGL_MATERIAL_H__ */