T2RenderContext_GL.cpp

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#include "ToshiPCH.h"
#include "T2RenderContext_GL.h"
#include "Math/TMatrix44.h"
 
//-----------------------------------------------------------------------------
// Enables memory debugging.
// Note: Should be the last include!
//-----------------------------------------------------------------------------
#include "Core/TMemoryDebugOn.h"
 
TOSHI_NAMESPACE_START
 
T2RenderContext::T2RenderContext()
{
    m_bDepthTest = TFALSE;
    glDisable( GL_DEPTH_TEST );
 
    m_bBlend = TFALSE;
    glDisable( GL_BLEND );
}
 
T2RenderContext::~T2RenderContext()
{
}
 
void T2RenderContext::ComputePerspectiveProjection( TMatrix44& a_rOutProjection, const T2Viewport& a_rViewportParams, const Projection& a_rProjParams )
{
    a_rOutProjection.m_f11 = ( a_rProjParams.vecProj.x * 2.0f ) / a_rViewportParams.GetWidth();
    a_rOutProjection.m_f12 = 0.0f;
    a_rOutProjection.m_f13 = 0.0f;
    a_rOutProjection.m_f14 = 0.0f;
    a_rOutProjection.m_f21 = 0.0f;
    a_rOutProjection.m_f22 = -( ( a_rProjParams.vecProj.y * 2.0f ) / a_rViewportParams.GetHeight() );
    a_rOutProjection.m_f23 = 0.0f;
    a_rOutProjection.m_f24 = 0.0f;
    a_rOutProjection.m_f31 = ( a_rProjParams.vecCenter.x * 2.0f ) / a_rViewportParams.GetWidth() - 1.0f;
    a_rOutProjection.m_f32 = -( ( a_rProjParams.vecCenter.y * 2.0f ) / a_rViewportParams.GetHeight() - 1.0f );
    a_rOutProjection.m_f33 = a_rProjParams.fFarClip / ( a_rProjParams.fFarClip - a_rProjParams.fNearClip );
    a_rOutProjection.m_f34 = 1.0f;
    a_rOutProjection.m_f41 = 0.0f;
    a_rOutProjection.m_f42 = 0.0f;
    a_rOutProjection.m_f43 = -( ( a_rProjParams.fNearClip * a_rProjParams.fFarClip ) / ( a_rProjParams.fFarClip - a_rProjParams.fNearClip ) );
    a_rOutProjection.m_f44 = 0.0f;
}
 
void T2RenderContext::ComputeOrthographicProjection( TMatrix44& a_rOutProjection, const T2Viewport& a_rViewportParams, const Projection& a_rProjParams )
{
    TASSERT( a_rProjParams.vecProj.x != 0.0f );
    TASSERT( a_rProjParams.vecProj.y != 0.0f );
    TASSERT( a_rViewportParams.GetWidth() != 0.0f );
    TASSERT( a_rViewportParams.GetHeight() != 0.0f );
 
    TASSERT( TMath::IsFinite( a_rProjParams.vecProj.x ) && ( !TMath::IsNaN( a_rProjParams.vecProj.x ) ) );
    TASSERT( TMath::IsFinite( a_rProjParams.vecProj.y ) && ( !TMath::IsNaN( a_rProjParams.vecProj.y ) ) );
    TASSERT( TMath::IsFinite( a_rProjParams.vecCenter.x ) && ( !TMath::IsNaN( a_rProjParams.vecCenter.x ) ) );
    TASSERT( TMath::IsFinite( a_rProjParams.vecCenter.y ) && ( !TMath::IsNaN( a_rProjParams.vecCenter.y ) ) );
 
    a_rOutProjection.m_f11 = ( a_rProjParams.vecProj.x * 2.0f ) / a_rViewportParams.GetWidth();
    a_rOutProjection.m_f12 = 0.0f;
    a_rOutProjection.m_f13 = 0.0f;
    a_rOutProjection.m_f14 = 0.0f;
    a_rOutProjection.m_f21 = 0.0f;
    a_rOutProjection.m_f22 = -( ( a_rProjParams.vecProj.y * 2.0f ) / a_rViewportParams.GetHeight() );
    a_rOutProjection.m_f23 = 0.0f;
    a_rOutProjection.m_f24 = 0.0f;
    a_rOutProjection.m_f31 = 0.0f;
    a_rOutProjection.m_f32 = 0.0f;
    a_rOutProjection.m_f33 = 1.0f / ( a_rProjParams.fFarClip - a_rProjParams.fNearClip );
    a_rOutProjection.m_f34 = 0.0f;
    a_rOutProjection.m_f41 = ( a_rProjParams.vecCenter.x * 2.0f ) / a_rViewportParams.GetWidth() - 1.0f;
    a_rOutProjection.m_f42 = -( ( a_rProjParams.vecCenter.y * 2.0f ) / a_rViewportParams.GetHeight() - 1.0f );
    a_rOutProjection.m_f43 = -( a_rProjParams.fNearClip / ( a_rProjParams.fFarClip - a_rProjParams.fNearClip ) );
    a_rOutProjection.m_f44 = 1.0f;
}
 
void T2RenderContext::ComputePerspectiveFrustum( Frustum& a_rcFrustum, const T2Viewport& a_rViewportParams, const Projection& a_rProjParams )
{
    TASSERT( a_rProjParams.vecProj.x != 0.0f );
    TASSERT( a_rProjParams.vecProj.y != 0.0f );
 
    TASSERT( TMath::IsFinite( a_rProjParams.vecProj.x ) && ( !TMath::IsNaN( a_rProjParams.vecProj.x ) ) );
    TASSERT( TMath::IsFinite( a_rProjParams.vecProj.y ) && ( !TMath::IsNaN( a_rProjParams.vecProj.y ) ) );
    TASSERT( TMath::IsFinite( a_rProjParams.vecCenter.x ) && ( !TMath::IsNaN( a_rProjParams.vecCenter.x ) ) );
    TASSERT( TMath::IsFinite( a_rProjParams.vecCenter.y ) && ( !TMath::IsNaN( a_rProjParams.vecCenter.y ) ) );
 
    TFLOAT   fVal1 = 1.0f / a_rProjParams.vecProj.x;
    TFLOAT   fVal2 = 1.0f / a_rProjParams.vecProj.y;
    TVector4 vec1  = TVector4( -a_rProjParams.vecCenter.x * fVal1, ( a_rViewportParams.GetHeight() - a_rProjParams.vecCenter.y ) * fVal2, 1.0f, 0.0f );
    TVector4 vec2  = TVector4( ( a_rViewportParams.GetWidth() - a_rProjParams.vecCenter.x ) * fVal1, vec1.y, 1.0f, 0.0f );
    TVector4 vec3  = TVector4( vec2.x, -a_rProjParams.vecCenter.y * fVal2, 1.0f, 0.0f );
    TVector4 vec4  = TVector4( vec1.x, vec3.y, 1.0f, 0.0f );
 
    // Setup planes
    a_rcFrustum[ FRUSTUMPLANE_LEFT ].AsVector4().CrossProduct( vec4, vec1 );
    a_rcFrustum[ FRUSTUMPLANE_RIGHT ].AsVector4().CrossProduct( vec2, vec3 );
    a_rcFrustum[ FRUSTUMPLANE_BOTTOM ].AsVector4().CrossProduct( vec3, vec4 );
    a_rcFrustum[ FRUSTUMPLANE_TOP ].AsVector4().CrossProduct( vec1, vec2 );
 
    // Normalize each plane
    a_rcFrustum[ FRUSTUMPLANE_LEFT ].AsNormal().Normalize();
    a_rcFrustum[ FRUSTUMPLANE_RIGHT ].AsNormal().Normalize();
    a_rcFrustum[ FRUSTUMPLANE_BOTTOM ].AsNormal().Normalize();
    a_rcFrustum[ FRUSTUMPLANE_TOP ].AsNormal().Normalize();
 
    // Setup near and far planes
    a_rcFrustum[ FRUSTUMPLANE_NEAR ].Set( 0.0f, 0.0f, -1.0f, -a_rProjParams.fNearClip );
    a_rcFrustum[ FRUSTUMPLANE_FAR ].Set( 0.0f, 0.0f, 1.0f, a_rProjParams.fFarClip );
}
 
void T2RenderContext::ComputeOrthographicFrustum( Frustum& a_rcFrustum, const T2Viewport& a_rViewportParams, const Projection& a_rProjParams )
{
    TASSERT( a_rProjParams.vecProj.x != 0.0f );
    TASSERT( a_rProjParams.vecProj.y != 0.0f );
    TASSERT( a_rViewportParams.GetWidth() != 0.0f );
    TASSERT( a_rViewportParams.GetHeight() != 0.0f );
 
    TASSERT( TMath::IsFinite( a_rProjParams.vecProj.x ) && ( !TMath::IsNaN( a_rProjParams.vecProj.x ) ) );
    TASSERT( TMath::IsFinite( a_rProjParams.vecProj.y ) && ( !TMath::IsNaN( a_rProjParams.vecProj.y ) ) );
    TASSERT( TMath::IsFinite( a_rProjParams.vecCenter.x ) && ( !TMath::IsNaN( a_rProjParams.vecCenter.x ) ) );
    TASSERT( TMath::IsFinite( a_rProjParams.vecCenter.y ) && ( !TMath::IsNaN( a_rProjParams.vecCenter.y ) ) );
 
    TFLOAT fWidth        = a_rViewportParams.GetWidth();
    TFLOAT fHeight       = a_rViewportParams.GetHeight();
    TFLOAT fCentreX      = a_rProjParams.vecCenter.x;
    TFLOAT fCentreY      = a_rProjParams.vecCenter.y;
    TFLOAT fProjXOverOne = 1.0f / a_rProjParams.vecProj.x;
    TFLOAT fProjYOverOne = 1.0f / a_rProjParams.vecProj.y;
 
    // Setup planes
    a_rcFrustum[ FRUSTUMPLANE_LEFT ].Set( -1.0f, 0.0f, 0.0f, fCentreX * fProjXOverOne );
    a_rcFrustum[ FRUSTUMPLANE_RIGHT ].Set( 1.0f, 0.0f, 0.0f, ( fWidth - fCentreX ) * fProjXOverOne );
    a_rcFrustum[ FRUSTUMPLANE_BOTTOM ].Set( 0.0f, -1.0f, 0.0f, fCentreY * fProjYOverOne );
    a_rcFrustum[ FRUSTUMPLANE_TOP ].Set( 0.0f, 1.0f, 0.0f, ( fHeight - fCentreY ) * fProjYOverOne );
    a_rcFrustum[ FRUSTUMPLANE_NEAR ].Set( 0.0f, 0.0f, -1.0f, -a_rProjParams.fNearClip );
    a_rcFrustum[ FRUSTUMPLANE_FAR ].Set( 0.0f, 0.0f, 1.0f, a_rProjParams.fFarClip );
}
 
TBOOL T2RenderContext::CullSphereToFrustumSimple( const TSphere& a_rSphere, const TPlane* a_pPlanes, TINT a_iNumPlanes )
{
    for ( TSIZE i = 0; i < FRUSTUMPLANE_NUMOF; i++ )
    {
        TFLOAT fDist = TVector4::DotProduct3( a_rSphere.AsVector4(), a_pPlanes[ i ].AsVector4() );
 
        if ( a_rSphere.GetRadius() < fDist - a_pPlanes[ i ].GetD() )
            return TFALSE;
    }
 
    return TTRUE;
}
 
TINT T2RenderContext::CullSphereToFrustum( const TSphere& a_rSphere, const TPlane* a_pPlanes, TINT a_iClipFlags, TINT a_iClipFlagsMask )
{
    TINT iLeftPlanes = a_iClipFlags & a_iClipFlagsMask;
    TINT iPlaneFlag  = 1;
 
    do {
        if ( iLeftPlanes == 0 )
        {
            return a_iClipFlags;
        }
 
        if ( iLeftPlanes & iPlaneFlag )
        {
            TFLOAT fDist = TVector4::DotProduct3( a_rSphere.AsVector4(), a_pPlanes->AsVector4() ) - a_pPlanes->GetD();
 
            if ( a_rSphere.GetRadius() < fDist )
            {
                return -1;
            }
 
            if ( fDist < -a_rSphere.GetRadius() )
            {
                a_iClipFlags &= ~iPlaneFlag;
            }
 
            iLeftPlanes &= ~iPlaneFlag;
        }
 
        iPlaneFlag = iPlaneFlag << 1;
        a_pPlanes++;
 
    } while ( TTRUE );
}
 
TBOOL T2RenderContext::SetShaderProgram( const T2Shader& a_rcShaderProgram )
{
    if ( m_uiCurrentShaderProgram != a_rcShaderProgram.GetProgram() )
    {
        a_rcShaderProgram.Use();
        m_uiCurrentShaderProgram = a_rcShaderProgram.GetProgram();
 
        return TTRUE;
    }
 
    return TFALSE;
}
 
GLuint T2RenderContext::GetTexture2D( TINT a_iTextureIndex )
{
    return m_aCurrentTextures[ a_iTextureIndex ];
}
 
void T2RenderContext::SetTexture2D( TINT a_iTextureIndex, GLuint a_uiTexture )
{
    if ( m_aCurrentTextures[ a_iTextureIndex ] != a_uiTexture )
    {
        if ( m_iCurrentTextureUnit != a_iTextureIndex )
        {
            glActiveTexture( GL_TEXTURE0 + a_iTextureIndex );
            m_iCurrentTextureUnit = a_iTextureIndex;
        }
 
        glBindTexture( GL_TEXTURE_2D, a_uiTexture );
        m_aCurrentTextures[ a_iTextureIndex ] = a_uiTexture;
    }
}
 
void T2RenderContext::SetTexture2D( TINT a_iTextureIndex, const T2GLTexture& a_rcTexture )
{
    SetTexture2D( a_iTextureIndex, a_rcTexture.GetHandle() );
}
 
void T2RenderContext::ResetTexture2D( TINT a_iTextureIndex )
{
    if ( m_iCurrentTextureUnit != a_iTextureIndex )
    {
        glActiveTexture( GL_TEXTURE0 + a_iTextureIndex );
        glBindTexture( GL_TEXTURE_2D, NULL );
 
        m_iCurrentTextureUnit                 = a_iTextureIndex;
        m_aCurrentTextures[ a_iTextureIndex ] = -1;
    }
}
 
void T2RenderContext::EnableDepthTest( TBOOL a_bEnable )
{
    if ( m_bDepthTest != a_bEnable )
    {
        if ( a_bEnable )
            glEnable( GL_DEPTH_TEST );
        else
            glDisable( GL_DEPTH_TEST );
 
        m_bDepthTest = a_bEnable;
    }
}
 
void T2RenderContext::EnableBlend( TBOOL a_bEnable )
{
    if ( m_bBlend != a_bEnable )
    {
        if ( a_bEnable )
            glEnable( GL_BLEND );
        else
            glDisable( GL_BLEND );
 
        m_bBlend = a_bEnable;
    }
}
 
TOSHI_NAMESPACE_END