renderstack::buffer Class Reference

wrapper for gl vertex and index buffers

#include <buffer.hpp>

Public Member Functions
	buffer (int gl_target, int gl_usage)
	buffer (int gl_target, int gl_usage, int gl_index_type, int gl_mode)
	~buffer ()
void	use () const
class vertex_format &	vertex_format ()
class vertex_format const &	vertex_format () const
int	count () const
int	gl_target () const
int	gl_usage () const
unsigned int	gl_buffer_object () const
int	gl_index_type () const
int	gl_mode () const
void	begin_edit ()
void	end_edit (uint32 end_index)
void	set_index (uint32 index)
void	put_float (vertex_attribute const &attribute, float x)
void	put_vec2 (vertex_attribute const &attribute, vec2 const &v)
void	put_vec2 (vertex_attribute const &attribute, float x, float y)
void	put_vec3 (vertex_attribute const &attribute, vec3 const &v)
void	put_vec3 (vertex_attribute const &attribute, float x, float y, float z)
void	put_vec4 (vertex_attribute const &attribute, vec4 const &v)
void	put_vec4 (vertex_attribute const &attribute, float x, float y, float z, float w)
void	put_uint16 (vertex_attribute const &attribute, uint16 x)
void	put_uint32 (vertex_attribute const &attribute, uint32 x)
void	put_position (vec3 const &v, int index=0)
void	put_position (float x, float y, float z, int index=0)
void	put_normal (vec3 const &v, int index=0)
void	put_normal (float x, float y, float z, int index=0)
void	put_texcoord (vec2 const &v, int index=0)
void	put_texcoord (float s, float t, int index=0)
void	put_index (uint32 index_location, uint32 index)
void	point (uint32 index0)
void	line (uint32 index0, uint32 index1)
void	triangle (uint32 index0, uint32 index1, uint32 index2)
void	quad (uint32 index0, uint32 index1, uint32 index2, uint32 index3)

---

Detailed Description

Definition at line 67 of file buffer.hpp.

---

Constructor & Destructor Documentation

renderstack::buffer::buffer	(	int	gl_target,
		int	gl_usage
	)

Definition at line 37 of file buffer.cpp.

:   m_gl_buffer_object  ((unsigned int)(~0))
,   m_gl_target         (gl_target)
,   m_gl_usage          (gl_usage)
{
    ::rs_gl_gen_buffers(1, &m_gl_buffer_object);
}

renderstack::buffer::buffer	(	int	gl_target,
		int	gl_usage,
		int	gl_index_type,
		int	gl_mode
	)

Definition at line 48 of file buffer.cpp.

:   m_gl_buffer_object  ((unsigned int)(~0))
,   m_gl_target         (gl_target)
,   m_gl_usage          (gl_usage)
,   m_gl_index_type     (gl_index_type)
,   m_gl_mode           (gl_mode)
{
    ::rs_gl_gen_buffers(1, &m_gl_buffer_object);
}

renderstack::buffer::~buffer

(

)

Definition at line 63 of file buffer.cpp.

{
    ::GLboolean is_buffer = ::rs_gl_is_buffer(m_gl_buffer_object);
    if(is_buffer != GL_FALSE)
    {
        ::rs_gl_delete_buffers(1, &m_gl_buffer_object);
    }
    else
    {
        ::rs_log("glIsBuffer() == GL_FALSE\n");
    }
}

---

Member Function Documentation

void renderstack::buffer::use

(

)

const

Definition at line 128 of file buffer.cpp.

{
    ::rs_gl_bind_buffer(
        gl_target(),
        gl_buffer_object()
    );
}

class vertex_format& renderstack::buffer::vertex_format

(

)

[inline]

Definition at line 76 of file buffer.hpp.

{ return m_vertex_format; }

class vertex_format const& renderstack::buffer::vertex_format

(

)

const [inline]

Definition at line 77 of file buffer.hpp.

{ return m_vertex_format; }

int renderstack::buffer::count

(

)

const [inline]

Definition at line 78 of file buffer.hpp.

{ return m_count; }

int renderstack::buffer::gl_target

(

)

const [inline]

Definition at line 79 of file buffer.hpp.

{ return m_gl_target; }

int renderstack::buffer::gl_usage

(

)

const [inline]

Definition at line 80 of file buffer.hpp.

{ return m_gl_usage; }

unsigned int renderstack::buffer::gl_buffer_object

(

)

const [inline]

Definition at line 81 of file buffer.hpp.

{ return m_gl_buffer_object; }

int renderstack::buffer::gl_index_type

(

)

const [inline]

Definition at line 82 of file buffer.hpp.

{ return m_gl_index_type; }

int renderstack::buffer::gl_mode

(

)

const [inline]

Definition at line 83 of file buffer.hpp.

{ return m_gl_mode; }

void renderstack::buffer::begin_edit

(

)

Definition at line 76 of file buffer.cpp.

{
    if(m_gl_target == GL_ARRAY_BUFFER)
    {
        m_stride = vertex_format().stride();
    }
    else if(m_gl_target == GL_ELEMENT_ARRAY_BUFFER)
    {
        m_stride = gl_size_of_type(gl_index_type());
    }
    else
    {
        throw invalid_buffer_gl_target_exception(m_gl_target);
    }

    if(m_stride == 0)
    {
        throw invalid_buffer_stride_exception();
    }

    m_current_index = 0;
}

void renderstack::buffer::end_edit

(

uint32

end_index

)

Definition at line 99 of file buffer.cpp.

{
    uint32 current_size = end_index * m_stride;

    if(current_size == 0)
    {
        return;
    }

    m_count = end_index;
    m_size  = current_size;

    ::rs_gl_bind_buffer(
        gl_target(), 
        gl_buffer_object()
    );

    ::rs_gl_buffer_data(
        gl_target(),   /*  gl target       */ 
        current_size,  /*  length          */ 
        &m_data[0],    /*  data pointer    */ 
        gl_usage()     /*  gl usage        */ 
    );

    /*  This will free the memory  */ 
    std::vector<unsigned char> dummy;
    m_data = dummy;
}

void renderstack::buffer::set_index

(

uint32

index

)

Definition at line 137 of file buffer.cpp.

{
    m_current_index = index;

    size_t offset = m_current_index * m_stride;

    /*  writing for example triangle writes 2 indices past current index  */ 
    if(offset + (4 * m_stride) > m_data.size())
    {
        size_t adjusted_capacity = m_data.size();

        /*  start with initial 32 kB  */ 
        if(adjusted_capacity == 0)
        {
            adjusted_capacity = 32 * 1024;
        }

        while(offset + (4 * m_stride) > adjusted_capacity)
        {
            adjusted_capacity *= 2;
        }
        if(adjusted_capacity != m_data.size())
        {
            m_data.resize(adjusted_capacity);
        }
    }
}

void renderstack::buffer::put_float	(	vertex_attribute const &	attribute,
		float	x
	)

Definition at line 165 of file buffer.cpp.

{
    size_t  offset   = m_current_index * m_stride + attribute.offset();
    float   *pointer = reinterpret_cast<float*>(&m_data[offset]);

    pointer[0] = x;
}

void renderstack::buffer::put_vec2	(	vertex_attribute const &	attribute,
		vec2 const &	v
	)

Definition at line 173 of file buffer.cpp.

{
    size_t  offset   = m_current_index * m_stride + attribute.offset();
    float   *pointer = reinterpret_cast<float*>(&m_data[offset]);

    pointer[0] = v.x;
    pointer[1] = v.y;
}

void renderstack::buffer::put_vec2	(	vertex_attribute const &	attribute,
		float	x,
		float	y
	)

Definition at line 182 of file buffer.cpp.

{
    size_t  offset   = m_current_index * m_stride + attribute.offset();
    float   *pointer = reinterpret_cast<float*>(&m_data[offset]);

    pointer[0] = x;
    pointer[1] = y;
}

void renderstack::buffer::put_vec3	(	vertex_attribute const &	attribute,
		vec3 const &	v
	)

Definition at line 191 of file buffer.cpp.

{
    size_t  offset   = m_current_index * m_stride + attribute.offset();
    float   *pointer = reinterpret_cast<float*>(&m_data[offset]);

    pointer[0] = v.x;
    pointer[1] = v.y;
    pointer[2] = v.z;
}

void renderstack::buffer::put_vec3	(	vertex_attribute const &	attribute,
		float	x,
		float	y,
		float	z
	)

Definition at line 201 of file buffer.cpp.

{
    size_t  offset   = m_current_index * m_stride + attribute.offset();
    float   *pointer = reinterpret_cast<float*>(&m_data[offset]);

    pointer[0] = x;
    pointer[1] = y;
    pointer[2] = z;
}

void renderstack::buffer::put_vec4	(	vertex_attribute const &	attribute,
		vec4 const &	v
	)

Definition at line 211 of file buffer.cpp.

{
    size_t  offset   = m_current_index * m_stride + attribute.offset();
    float   *pointer = reinterpret_cast<float*>(&m_data[offset]);

    pointer[0] = v.x;
    pointer[1] = v.y;
    pointer[2] = v.z;
    pointer[3] = v.w;
}

void renderstack::buffer::put_vec4	(	vertex_attribute const &	attribute,
		float	x,
		float	y,
		float	z,
		float	w
	)

Definition at line 222 of file buffer.cpp.

{
    size_t  offset   = m_current_index * m_stride + attribute.offset();
    float   *pointer = reinterpret_cast<float*>(&m_data[offset]);

    pointer[0] = x;
    pointer[1] = y;
    pointer[2] = z;
    pointer[3] = w;
}

void renderstack::buffer::put_uint16	(	vertex_attribute const &	attribute,
		uint16	x
	)

Definition at line 233 of file buffer.cpp.

{
    size_t  offset   = m_current_index * m_stride + attribute.offset();
    uint16  *pointer = reinterpret_cast<uint16*>(&m_data[offset]);

    pointer[0] = x;
}

void renderstack::buffer::put_uint32	(	vertex_attribute const &	attribute,
		uint32	x
	)

Definition at line 241 of file buffer.cpp.

{
    size_t  offset   = m_current_index * m_stride + attribute.offset();
    uint32  *pointer = reinterpret_cast<uint32*>(&m_data[offset]);

    pointer[0] = x;
}

void renderstack::buffer::put_position	(	vec3 const &	v,
		int	index = 0
	)

Definition at line 249 of file buffer.cpp.

{
    vertex_attribute const &attribute = vertex_format().attribute(
        vertex_attribute_usage_position,
        index
    );

    put_vec3(attribute, v);
}

void renderstack::buffer::put_position	(	float	x,
		float	y,
		float	z,
		int	index = 0
	)

Definition at line 259 of file buffer.cpp.

{
    vertex_attribute const &attribute = vertex_format().attribute(
        vertex_attribute_usage_position,
        index
    );

    put_vec3(attribute, x, y, z);
}

void renderstack::buffer::put_normal	(	vec3 const &	v,
		int	index = 0
	)

Definition at line 269 of file buffer.cpp.

{
    vertex_attribute const &attribute = vertex_format().attribute(
        vertex_attribute_usage_normal,
        index
    );

    put_vec3(attribute, v);
}

void renderstack::buffer::put_normal	(	float	x,
		float	y,
		float	z,
		int	index = 0
	)

Definition at line 279 of file buffer.cpp.

{
    vertex_attribute const &attribute = vertex_format().attribute(
        vertex_attribute_usage_normal,
        index
    );

    put_vec3(attribute, x, y, z);
}

void renderstack::buffer::put_texcoord	(	vec2 const &	v,
		int	index = 0
	)

Definition at line 289 of file buffer.cpp.

{
    vertex_attribute const &attribute = vertex_format().attribute(
        vertex_attribute_usage_texcoord,
        index
    );

    put_vec2(attribute, v);
}

void renderstack::buffer::put_texcoord	(	float	s,
		float	t,
		int	index = 0
	)

Definition at line 299 of file buffer.cpp.

{
    vertex_attribute const &attribute = vertex_format().attribute(
        vertex_attribute_usage_texcoord,
        index
    );

    put_vec2(attribute, s, t);
}

void renderstack::buffer::put_index	(	uint32	index_location,
		uint32	index
	)

Definition at line 309 of file buffer.cpp.

{
    switch(m_stride)
    {
        case 1:
        {
            size_t    offset   = index_location * m_stride;
            ::GLubyte *pointer = reinterpret_cast<::GLubyte*>(&m_data[offset]);

            if(
                (index_value > 0xff) 
            )
            {
                throw index_out_of_range_exception();
            }

            pointer[0] = static_cast<::GLubyte>(index_value & 0xff);

            break;
        }
        case 2:
        {
            size_t     offset   = index_location * m_stride;
            ::GLushort *pointer = reinterpret_cast<::GLushort*>(&m_data[offset]);

            if(
                (index_value > 0xffff) 
            )
            {
                throw index_out_of_range_exception();
            }

            pointer[0] = static_cast<::GLushort>(index_value & 0xffff);

            break;
        }
        case 4:
        {
            size_t   offset   = index_location * m_stride;
            ::GLuint *pointer = reinterpret_cast<::GLuint*>(&m_data[offset]);

            pointer[0] = index_value;

            break;
        }
        default:
        {
            throw invalid_buffer_stride_exception();
        }
    }
}

void renderstack::buffer::point

(

uint32

index0

)

Definition at line 361 of file buffer.cpp.

{
    put_index(m_current_index, index0);
}

void renderstack::buffer::line	(	uint32	index0,
		uint32	index1
	)

Definition at line 366 of file buffer.cpp.

{
    put_index(m_current_index    , index0);
    put_index(m_current_index + 1, index1);
}

void renderstack::buffer::triangle	(	uint32	index0,
		uint32	index1,
		uint32	index2
	)

Definition at line 372 of file buffer.cpp.

{
    put_index(m_current_index    , index0);
    put_index(m_current_index + 1, index1);
    put_index(m_current_index + 2, index2);
}

void renderstack::buffer::quad	(	uint32	index0,
		uint32	index1,
		uint32	index2,
		uint32	index3
	)

Definition at line 379 of file buffer.cpp.

{
    put_index(m_current_index    , index0);
    put_index(m_current_index + 1, index1);
    put_index(m_current_index + 2, index2);
    put_index(m_current_index + 3, index0);
    put_index(m_current_index + 4, index2);
    put_index(m_current_index + 5, index3);
}

---

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

• buffer.hpp
• buffer.cpp