Beatmup::ImageShader Class Reference

A GLSL program to process images. More...

#include <image_shader.h>

Inheritance diagram for Beatmup::ImageShader:

Classes
class	NoSource
	Expection thrown if no shader source is provided. More...

Public Member Functions
	ImageShader (GL::RecycleBin &recycleBin)
	ImageShader (Context &ctx)
	~ImageShader ()
void	setSourceCode (const std::string &sourceCode)
	Passes new source code to the fragment shader. More...
void	setOutputClipping (const IntRectangle &rectangle)
	Sets output clipping area. More...
void	prepare (GraphicPipeline &gpu, GL::TextureHandler *input, const TextureParam texParam, AbstractBitmap *output, const AffineMapping &mapping)
	Conducts required preparations for blending. More...
void	prepare (GraphicPipeline &gpu, GL::TextureHandler *input, AbstractBitmap *output)
void	prepare (GraphicPipeline &gpu, AbstractBitmap *output)
	Conducts required preparations for blending. More...
void	bindSamplerArray (const char *uniformId, int startingUnit, int numUnits)
	Binds a bunch of texture units to a uniform sampler array variable. More...
void	process (GraphicPipeline &gpu)
	Apply the shader to produce an image. More...
bool	usesContext (Context &context) const
	Returns true if the shader has ressources attached to a given context. More...
Public Member Functions inherited from Beatmup::GL::VariablesBundle
void	clear ()
	Removes all stored variables. More...
void	setInteger (std::string name, int value)
	Sets a scalar integer uniform value. More...
void	setInteger (std::string name, int x, int y)
void	setInteger (std::string name, int x, int y, int z)
void	setInteger (std::string name, int x, int y, int z, int w)
void	setFloat (std::string name, float value)
	Sets a scalar float uniform value. More...
void	setFloat (std::string name, float x, float y)
void	setFloat (std::string name, float x, float y, float z)
void	setFloat (std::string name, float x, float y, float z, float w)
void	setFloatMatrix2 (std::string name, const float matrix[4])
	Sets a float 2*2 matrix variable value. More...
void	setFloatMatrix3 (std::string name, const float matrix[9])
	Sets a float 3*3 matrix variable value. More...
void	setFloatMatrix4 (std::string name, const float matrix[16])
	Sets a float 4*4 matrix variable value. More...
void	setFloatMatrix4 (std::string name, const Color::Matrix &matrix)
	Sets a float 4*4 matrix variable value from a Color::Matrix instance. More...
void	setFloatArray (std::string name, const std::vector< float > &values)
	Sets a float array variable value. More...
float	getFloat (const std::string &name) const
	Retrieves a value of a scalar float uniform variable by its name. More...
Public Member Functions inherited from Beatmup::LockableObject
void	lock ()
void	unlock ()
Public Member Functions inherited from Beatmup::Object
virtual	~Object ()

Static Public Attributes
static const std::string	INPUT_IMAGE_DECL_TYPE = GL::FragmentShader::DIALECT_SAMPLER_DECL_TYPE
	A virtual input image type defined at shader compile time by ordinary texture or OES texture sampler depending on the input bound. More...
static const std::string	INPUT_IMAGE_ID = "image"
	Shader variable name referring to the input image. More...
static const std::string	CODE_HEADER
	Shader code header containing necessary declarations. More...

Private Member Functions
	ImageShader (const ImageShader &)=delete
	disabling copying constructor More...

Private Attributes
GL::RecycleBin &	recycleBin
GL::RenderingProgram *	program
std::string	sourceCode
	last passed fragment shader source code More...
bool	upToDate
	if true, the program is up-to-date with respect to the source code More...
GL::TextureHandler::TextureFormat	inputFormat
	last used input texture format; when changed, the shader is recompiled More...
IntRectangle	outputClipRect
	output clip rectangle: only this specified area of the output image will be changed More...

Additional Inherited Members
Protected Member Functions inherited from Beatmup::GL::VariablesBundle
void	apply (Program &program)

Detailed Description

A GLSL program to process images.

Definition at line 34 of file image_shader.h.

Constructor & Destructor Documentation

ImageShader() [1/3]

Beatmup::ImageShader::ImageShader ( const ImageShader &  )

privatedelete

disabling copying constructor

ImageShader() [2/3]

ImageShader::ImageShader

(

GL::RecycleBin &

recycleBin

)

Definition at line 55 of file image_shader.cpp.

                                                 :
    recycleBin(recycleBin),
    program(nullptr),
    upToDate(false),
    inputFormat(GL::TextureHandler::TextureFormat::RGBx8)
{}

ImageShader() [3/3]

ImageShader::ImageShader

(

Context &

ctx

)

Definition at line 63 of file image_shader.cpp.

                                     :
    ImageShader(*ctx.getGpuRecycleBin())
{}

~ImageShader()

ImageShader::~ImageShader

(

)

Definition at line 68 of file image_shader.cpp.

                          {
    recycleBin.put(program);
}

Member Function Documentation

setSourceCode()

void ImageShader::setSourceCode

(

const std::string &

sourceCode

)

Passes new source code to the fragment shader.

The new source code will be compiled and linked when next rendering occurs.

Definition at line 73 of file image_shader.cpp.

                                                           {
    lock();
    this->sourceCode = sourceCode;
    upToDate = false;
    unlock();
}

setOutputClipping()

void ImageShader::setOutputClipping

(

const IntRectangle &

rectangle

)

Sets output clipping area.

Only this specified area of the output bitmap will be changed by executing the shader. This must be called before prepare().

Parameters

[in]

rectangle

The output clipping area in pixels

Definition at line 81 of file image_shader.cpp.

                                                                 {
    this->outputClipRect = rectangle;
}

prepare() [1/3]

void ImageShader::prepare	(	GraphicPipeline &	gpu,
		GL::TextureHandler *	input,
		const TextureParam	texParam,
		AbstractBitmap *	output,
		const AffineMapping &	mapping
	)

Conducts required preparations for blending.

Compiles shaders and links the rendering program if not yet.

Parameters

gpu	Graphic pipeline instance
input	Shader input image. This is optional, but the shader is considered to have at least one input image if this function is used.
texParam	Input texture parameter
output	Image to write shader output to (optional)
mapping	Geometric transformation to apply when filling output

Definition at line 86 of file image_shader.cpp.

                                                                                                                                                          {
    LockGuard lock(this);
    if (sourceCode.empty())
        throw NoSource();
 
    // check if the input format changes
    if (input && input->getTextureFormat() != inputFormat)
        upToDate = false;
 
 
    // make program ready if not yet or if not up to date
    if (!program || !upToDate) {
        inputFormat = input ? input->getTextureFormat() : GL::TextureHandler::TextureFormat::RGBx8;
 
        // link program
        GL::Extensions textureExtension = inputFormat == GL::TextureHandler::TextureFormat::OES_Ext ? GL::Extensions::EXTERNAL_TEXTURE : GL::Extensions::NONE;
        GL::FragmentShader fragmentShader(gpu, sourceCode, GL::Extensions::BEATMUP_DIALECT + textureExtension);
        if (!program) {
            program = new GL::RenderingProgram(gpu, fragmentShader);
        }
        else {
            program->link(gpu, fragmentShader);
        }
 
        upToDate = true;
    }
 
    // enable program
    program->enable(gpu);
    if (input)
        program->setInteger(INPUT_IMAGE_ID, 0);
    gpu.setTextureCoordinates(Rectangle::UNIT_SQUARE);
 
    // bind output
    if (output) {
        if (!outputClipRect.empty())
            gpu.bindOutput(*output, outputClipRect);
        else
            gpu.bindOutput(*output);
    }
 
    // bind input
    if (input)
        gpu.bind(*input, 0, texParam);
        // Binding order matters: texture unit 0 is used for input now.
 
    program->setMatrix3(
        GL::RenderingPrograms::MODELVIEW_MATRIX_ID,
        !output || outputClipRect.empty() ? mapping :
          (getOutputCropMapping(output ? output->getSize() : gpu.getDisplayResolution(), outputClipRect) * mapping)
    );
 
    // apply bundle
    apply(*program);
}

prepare() [2/3]

void ImageShader::prepare	(	GraphicPipeline &	gpu,
		GL::TextureHandler *	input,
		AbstractBitmap *	output
	)

Definition at line 143 of file image_shader.cpp.

                                                                                               {
    prepare(gpu, input, TextureParam::INTERP_LINEAR, output, AffineMapping::IDENTITY);
}

prepare() [3/3]

void ImageShader::prepare	(	GraphicPipeline &	gpu,
		AbstractBitmap *	output
	)

Conducts required preparations for blending.

Compiles shaders and links the rendering program if not yet. This function is used for shaders having no inputs.

Parameters

gpu	Graphic pipeline instance
output	Image to write shader output to (optional)

Definition at line 148 of file image_shader.cpp.

                                                                      {
    LockGuard lock(this);
    if (sourceCode.empty())
        throw NoSource();
 
    // link program if not yet
    if (!program || !upToDate) {
        // link program
        GL::FragmentShader fragmentShader(gpu, sourceCode, GL::Extensions::BEATMUP_DIALECT);
        if (!program) {
            program = new GL::RenderingProgram(gpu, fragmentShader);
        }
        else {
            program->link(gpu, fragmentShader);
        }
 
        upToDate = true;
    }
 
    // enable program
    program->enable(gpu);
 
    // bind output
    if (output) {
        if (!outputClipRect.empty())
            gpu.bindOutput(*output, outputClipRect);
        else
            gpu.bindOutput(*output);
    }
 
    // set up mapping
    program->setMatrix3(
        GL::RenderingPrograms::MODELVIEW_MATRIX_ID,
        !output || outputClipRect.empty() ? AffineMapping::IDENTITY :
          getOutputCropMapping(output ? output->getSize() : gpu.getDisplayResolution(), outputClipRect)
    );
 
    // apply bundle
    apply(*program);
}

bindSamplerArray()

void ImageShader::bindSamplerArray	(	const char *	uniformId,
		int	startingUnit,
		int	numUnits
	)

Binds a bunch of texture units to a uniform sampler array variable.

Parameters

[in]	uniformId	The uniform array variable name
[in]	startingUnit	First texture unit to be bound to the first element of the array
[in]	numUnits	Number of texture units to bind (likely matches the length of the array)

Definition at line 190 of file image_shader.cpp.

                                                                                        {
    program->setIntegerArray(uniformId, startingUnit, numUnits);
}

process()

void ImageShader::process

(

GraphicPipeline &

gpu

)

Apply the shader to produce an image.

Parameters

gpu	A graphic pipeline instance

Definition at line 195 of file image_shader.cpp.

                                              {
    program->blend();
}

usesContext()

bool Beatmup::ImageShader::usesContext ( Context &  context ) const

inline

Returns true if the shader has ressources attached to a given context.

Definition at line 98 of file image_shader.h.

{ return context.getGpuRecycleBin() == &recycleBin; }

Member Data Documentation

recycleBin

GL::RecycleBin& Beatmup::ImageShader::recycleBin

private

Definition at line 37 of file image_shader.h.

program

GL::RenderingProgram* Beatmup::ImageShader::program

private

Definition at line 38 of file image_shader.h.

sourceCode

std::string Beatmup::ImageShader::sourceCode

private

last passed fragment shader source code

Definition at line 39 of file image_shader.h.

upToDate

bool Beatmup::ImageShader::upToDate

private

if true, the program is up-to-date with respect to the source code

Definition at line 40 of file image_shader.h.

inputFormat

GL::TextureHandler::TextureFormat Beatmup::ImageShader::inputFormat

private

last used input texture format; when changed, the shader is recompiled

Definition at line 41 of file image_shader.h.

outputClipRect

IntRectangle Beatmup::ImageShader::outputClipRect

private

output clip rectangle: only this specified area of the output image will be changed

Definition at line 42 of file image_shader.h.

INPUT_IMAGE_DECL_TYPE

const std::string ImageShader::INPUT_IMAGE_DECL_TYPE = GL::FragmentShader::DIALECT_SAMPLER_DECL_TYPE

static

A virtual input image type defined at shader compile time by ordinary texture or OES texture sampler depending on the input bound.

Definition at line 104 of file image_shader.h.

INPUT_IMAGE_ID

const std::string ImageShader::INPUT_IMAGE_ID = "image"

static

Shader variable name referring to the input image.

Definition at line 109 of file image_shader.h.

CODE_HEADER

const std::string ImageShader::CODE_HEADER

static

Initial value:

=
        "uniform " + INPUT_IMAGE_DECL_TYPE + " " + INPUT_IMAGE_ID +";\n" +
        GL::RenderingPrograms::DECLARE_TEXTURE_COORDINATES_IN_FRAG

Shader code header containing necessary declarations.

Definition at line 114 of file image_shader.h.

---

The documentation for this class was generated from the following files:

• core/shading/image_shader.h
• core/shading/image_shader.cpp