source: trunk/src/gfx/debug_draw.cc @ 491

// Copyright (C) 2014-2015 ChaosForge Ltd
// http://chaosforge.org/
//
// This file is part of Nova libraries. 
// For conditions of distribution and use, see copying.txt file in root folder.

#include "nv/gfx/debug_draw.hh"

#include "nv/interface/device.hh"
#include "nv/core/logging.hh"

static const char *nv_debug_draw_vertex_shader = R"(
#version 120
attribute vec3 nv_position;
attribute vec3 nv_color;
varying vec3 v_color;
uniform mat4 nv_m_mvp;
void main(void)
{
        gl_Position = nv_m_mvp * vec4 (nv_position, 1.0);
        v_color     = nv_color;
};
)";
static const char *nv_debug_draw_fragment_shader = R"(
#version 120
varying vec3 v_color;
out vec4 o_frag_color;
void main(void)
{
        o_frag_color = vec4( v_color, 1.0 );
}
)";

nv::debug_data::debug_data( context* a_context )
        : m_context( a_context ), m_program(), m_va()
{
        m_program = m_context->get_device()->create_program( nv_debug_draw_vertex_shader, nv_debug_draw_fragment_shader );
        m_buffer_size = 0;
}

void nv::debug_data::update()
{
        if ( !m_va.is_valid() || m_data.size() > m_buffer_size )
        {
                if ( m_va.is_valid() ) m_context->release( m_va );
                m_buffer_size = nv::max( m_data.size(), 4096U, m_buffer_size );
                m_vb = m_context->get_device()->create_buffer( VERTEX_BUFFER, nv::STREAM_DRAW, m_buffer_size * sizeof( debug_vtx ), m_data.data() );
                vertex_array_desc va_desc;
                va_desc.add_vertex_buffers< debug_vtx >( m_vb, true );
                m_va = m_context->create_vertex_array( va_desc );
        }
        else
        {
                m_context->update( m_vb, m_data.data(), 0, m_data.size()* sizeof( debug_vtx ) );
        }
}

void nv::debug_data::reset()
{
        m_data.clear();
}

void nv::debug_data::push_line( const vec3& a, const vec3& b, const vec3& color )
{
        m_data.emplace_back( a, color );
        m_data.emplace_back( b, color );
}

void nv::debug_data::push_aabox( const vec3& a, const vec3& b, const vec3& color )
{
        vec3 corners[8] =
        {
                vec3( a.x, a.y, a.z ), vec3( b.x, a.y, a.z ), vec3( b.x, a.y, b.z ), vec3( a.x, a.y, b.z ),
                vec3( a.x, b.y, a.z ), vec3( b.x, b.y, a.z ), vec3( b.x, b.y, b.z ), vec3( a.x, b.y, b.z ),
        };

        push_line( corners[0], corners[1], color );
        push_line( corners[1], corners[2], color );
        push_line( corners[2], corners[3], color );
        push_line( corners[3], corners[0], color );
        push_line( corners[0], corners[4], color );
        push_line( corners[1], corners[5], color );
        push_line( corners[2], corners[6], color );
        push_line( corners[3], corners[7], color );
        push_line( corners[4], corners[5], color );
        push_line( corners[5], corners[6], color );
        push_line( corners[6], corners[7], color );
        push_line( corners[7], corners[4], color );
}

nv::debug_data::~debug_data()
{
        m_context->release( m_va );
        m_context->get_device()->release( m_program );
}