x3d_texture_gl.cpp

#include "x3d_texture_gl.h"
#include <cassert>
#include <cstring>

X3D::X3DTextureGL::X3DTextureGL(int width, int height, X3DTextureFormat fmt, int levels) :
    X3DTexture(width, height, fmt, levels)
{
    glGenTextures(1, &m_texture);
    m_pbos = new GLuint[m_levels];
}

X3D::X3DTextureGL::~X3DTextureGL()
{
    glDeleteTextures(1, &m_texture);
    delete[] m_pbos;
}

void X3D::X3DTextureGL::Upload(uint8_t *data, size_t size, int level)
{
    assert(level < m_levels);
    glBindTexture(GL_TEXTURE_2D, m_texture);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
    glPixelStorei(GL_UNPACK_ALIGNMENT, 1);

    switch (m_fmt) {
        case X3D_FMT_ARGB8:
            glTexImage2D(GL_TEXTURE_2D,
                level,
                GL_RGBA8,
                Get_Width(level),
                Get_Height(level),
                0,
                GL_BGRA,
                GL_UNSIGNED_INT_8_8_8_8_REV,
                data);
            break;
        case X3D_FMT_RGBA8:
            glTexImage2D(GL_TEXTURE_2D,
                level,
                GL_RGBA8,
                Get_Width(level),
                Get_Height(level),
                0,
                GL_RGBA,
                GL_UNSIGNED_INT_8_8_8_8,
                data);
            break;
        case X3D_FMT_RGB8:
            glTexImage2D(GL_TEXTURE_2D,
                level,
                GL_RGB8,
                Get_Width(level),
                Get_Height(level),
                0,
                GL_RGB,
                GL_UNSIGNED_INT_8_8_8_8,
                data);
            break;
        case X3D_FMT_RGBA16F:
            glTexImage2D(GL_TEXTURE_2D, level, GL_RGBA16F, Get_Width(level), Get_Height(level), 0, GL_RGBA, GL_FLOAT, data);
            break;
        case X3D_FMT_RGB16F:
            glTexImage2D(GL_TEXTURE_2D, level, GL_RGB16F, Get_Width(level), Get_Height(level), 0, GL_RGB, GL_FLOAT, data);
            break;
        case X3D_FMT_RGBA32F:
            glTexImage2D(GL_TEXTURE_2D, level, GL_RGBA32F, Get_Width(level), Get_Height(level), 0, GL_RGBA, GL_FLOAT, data);
            break;
        case X3D_FMT_RGB32F:
            glTexImage2D(GL_TEXTURE_2D, level, GL_RGB32F, Get_Width(level), Get_Height(level), 0, GL_RGB, GL_FLOAT, data);
            break;
        case X3D_FMT_BC1:
            glCompressedTexImage2D(
                GL_TEXTURE_2D, level, GL_COMPRESSED_RGBA_S3TC_DXT1_EXT, Get_Width(level), Get_Height(level), 0, size, data);
            break;
        case X3D_FMT_BC3:
            glCompressedTexImage2D(
                GL_TEXTURE_2D, level, GL_COMPRESSED_RGBA_S3TC_DXT5_EXT, Get_Width(level), Get_Height(level), 0, size, data);
            break;
        default:
            break;
    }
}

void *X3D::X3DTextureGL::Lock(X3DLockUsage usage, int level)
{
    assert(level < m_levels);
    glGenBuffers(1, &m_pbos[level]);
    glBindBuffer(GL_PIXEL_UNPACK_BUFFER, m_pbos[level]);
    glBufferData(GL_PIXEL_UNPACK_BUFFER, Get_Bytesize(level), nullptr, GL_STREAM_DRAW);
    return glMapBuffer(GL_PIXEL_UNPACK_BUFFER, (usage == X3D_LOCK_WRITE) ? GL_WRITE_ONLY : GL_READ_ONLY);
}

void X3D::X3DTextureGL::Unlock(int level)
{
    assert(level < m_levels);
    // Copy changes to texture
    glBindBuffer(GL_PIXEL_UNPACK_BUFFER, m_pbos[level]);

    if (glUnmapBuffer(GL_PIXEL_UNPACK_BUFFER) == GL_FALSE)
    {
        const GLchar *msg = "Failed to unmap array buffer";
        glDebugMessageInsertARB(
            GL_DEBUG_SOURCE_APPLICATION_ARB, GL_DEBUG_TYPE_ERROR_ARB, 0, GL_DEBUG_SEVERITY_HIGH_ARB, strlen(msg), msg);
    }
    Upload(nullptr, Get_Bytesize(level), level);
    glBindBuffer(GL_PIXEL_UNPACK_BUFFER, 0);
    glDeleteBuffers(1, &m_pbos[level]);
}

void X3D::X3DTextureGL::Bind(int slot)
{
    glBindTexture(GL_TEXTURE_2D, m_texture);
}

void X3D::X3DTextureGL::Unbind(int slot)
{
    glBindTexture(GL_TEXTURE_2D, 0);
}