managed_frame_buffer.cxx

#include "managed_frame_buffer.h"
 
namespace cgv {
namespace render {
 
managed_frame_buffer::managed_frame_buffer() {
 
    index_counter = 0;
    size = ivec2(0);
}
 
managed_frame_buffer::~managed_frame_buffer() {
 
    attachments.clear();
}
 
void managed_frame_buffer::destruct(const context& ctx) {
 
    fb.destruct(ctx);
 
    index_counter = 0;
    for(auto it = attachments.begin(); it != attachments.end(); ++it) {
        attachment& a = (*it).second;
        a.tex.destruct(ctx);
    }
}
 
ivec2 managed_frame_buffer::get_size() {
 
    return ivec2(fb.get_width(), fb.get_height());
}
 
bool managed_frame_buffer::set_size(const ivec2& size) {
 
    // TODO: need gl_context for that but cannot include it in this lib
    //GLint max_render_buffer_size;
    //glGetIntegerv(GL_MAX_RENDERBUFFER_SIZE, &max_render_buffer_size);
 
    int max_render_buffer_size = 12288;
 
    // TODO: in static builds (exe) the max render buffer size does not return useful values when this method is called in a drawable constructor
    if(max_render_buffer_size > 0) {
        if(size.x() > max_render_buffer_size || size.y() > max_render_buffer_size) {
            this->size = ivec2(-1);
            return false;
        }
    }
    this->size = size;
    return true;
}
 
void managed_frame_buffer::add_attachment(const std::string& name, const std::string& format, TextureFilter tf, TextureWrap tw, bool attach) {
 
    attachment a;
    a.attach = attach;
    a.format = format;
    a.tf = tf;
    a.tw = tw;
 
    if(a.is_depth_attachment()) {
        a.index = 0;
    } else {
        a.index = index_counter;
        ++index_counter;
    }
 
    attachments.insert(std::make_pair(name, a));
}
 
bool managed_frame_buffer::enable_attachment(context& ctx, const std::string& name, int tex_unit) {
 
    auto elem = attachments.find(name);
    if(elem != attachments.end()) {
        attachment& a = (*elem).second;
        return a.tex.enable(ctx, tex_unit);
    }
 
    return false;
}
 
bool managed_frame_buffer::disable_attachment(context& ctx, const std::string& name) {
 
    auto elem = attachments.find(name);
    if(elem != attachments.end()) {
        attachment& a = (*elem).second;
        return a.tex.disable(ctx);
    }
 
    return false;
}
 
texture* managed_frame_buffer::attachment_texture_ptr(const std::string& name) {
 
    auto elem = attachments.find(name);
    if(elem != attachments.end()) {
        attachment& a = (*elem).second;
        return &a.tex;
    }
 
    return nullptr;
}
 
bool managed_frame_buffer::ensure(context& ctx) {
 
    ivec2 actual_size = get_actual_size(ctx);
 
    if(!fb.is_created() || fb.get_width() != actual_size.x() || fb.get_height() != actual_size.y()) {
        destruct(ctx);
        if(!create_and_validate(ctx, actual_size)) {
            std::cerr << "Error: fbo not complete" << std::endl;
            abort();
        }
        return true;
    }
 
    return false;
}
 
bool managed_frame_buffer::enable(context& ctx) {
 
    bool success = fb.enable(ctx);
    fb.push_viewport(ctx);
    return success;
}
 
bool managed_frame_buffer::disable(context& ctx) {
 
    fb.pop_viewport(ctx);
    return fb.disable(ctx);
}
 
bool managed_frame_buffer::create_and_validate(context& ctx, const ivec2& size) {
 
    fb.create(ctx, size.x(), size.y());
 
    for(auto it = attachments.begin(); it != attachments.end(); ++it) {
        attachment& a = (*it).second;
 
        unsigned filter_specifier = (unsigned)a.tf;
 
        // even filter specifiers are nearest and odd are linear
        TextureFilter mag_filter = (filter_specifier & 1) ? TF_LINEAR : TF_NEAREST;
        // specifiers larger than 1 are using mipmaps
        bool use_mipmaps = filter_specifier > 1;
 
        a.tex = texture(a.format, mag_filter, a.tf, a.tw, a.tw);
        a.tex.create(ctx, TT_2D, size.x(), size.y());
 
        if(use_mipmaps)
            a.tex.generate_mipmaps(ctx);
 
        if(a.is_depth_attachment()) {
            fb.attach(ctx, a.tex);
        } else {
            if(a.attach) {
                fb.attach(ctx, a.tex, 0, a.index);
            }
        }
    }
 
    return fb.is_complete(ctx);
}
 
ivec2 managed_frame_buffer::get_actual_size(context& ctx) {
 
    ivec2 actual_size(size);
    if(size.x() <= 0)
        actual_size.x() = ctx.get_width();
    if(size.y() <= 0)
        actual_size.y() = ctx.get_height();
    return actual_size;
}
 
}
}