canvas_overlay.cxx

#include "canvas_overlay.h"
 
using namespace cgv::render;
 
namespace cgv {
namespace app {
 
canvas_overlay::canvas_overlay() : overlay() {
 
    blit_style_.use_blending = true;
    blit_style_.use_texture = true;
    blit_style_.feather_width = 0.0f;
}
 
bool canvas_overlay::init(context& ctx) {
    
    bool success = true;
 
    frame_buffer_.add_attachment("color", "uint8[R,G,B,A]");
    frame_buffer_.set_size(get_rectangle().size);
    success &= frame_buffer_.ensure(ctx);
 
    content_canvas.set_apply_gamma(false);
    success &= content_canvas.init(ctx);
 
    overlay_canvas.register_shader("rectangle", cgv::g2d::shaders::rectangle);
    success &= overlay_canvas.init(ctx);
 
    init_styles();
 
    return success;
}
 
void canvas_overlay::clear(context& ctx) {
 
    content_canvas.destruct(ctx);
    overlay_canvas.destruct(ctx);
    frame_buffer_.destruct(ctx);
}
 
void canvas_overlay::on_set(void* member_ptr) {
 
    handle_member_change(cgv::utils::pointer_test(member_ptr));
    update_member(member_ptr);
    post_damage();
}
 
void canvas_overlay::after_finish(context& ctx) {
 
    if(is_visible())
        draw_impl(ctx);
}
 
void canvas_overlay::register_shader(const std::string& name, const std::string& filename) {
 
    content_canvas.register_shader(name, filename);
}
 
void canvas_overlay::post_damage(bool redraw) {
    has_damage_ = true;
    if(redraw)
        post_redraw();
}
 
ivec2 canvas_overlay::get_local_mouse_pos(ivec2 mouse_pos) const {
    ivec2 pos = cgv::g2d::change_origin(mouse_pos, get_viewport_size(), cgv::g2d::CoordinateOrigin::kUpperLeft, overlay_canvas.get_origin_setting());
    pos -= get_rectangle().position;
    pos = cgv::g2d::change_origin(pos, get_rectangle().size, overlay_canvas.get_origin_setting(), content_canvas.get_origin_setting());
    return pos;
}
 
bool canvas_overlay::is_hit(const ivec2& mouse_pos) const {
    ivec2 test_pos = cgv::g2d::change_origin(mouse_pos, get_viewport_size(), cgv::g2d::CoordinateOrigin::kUpperLeft, overlay_canvas.get_origin_setting());
    return get_rectangle().contains(test_pos);
}
 
bool canvas_overlay::is_hit_local(const ivec2& local_mouse_pos) const {
    return get_rectangle().contains(local_mouse_pos);
}
 
bool canvas_overlay::ensure_layout(context& ctx) {
 
    if(overlay::ensure_layout(ctx) || recreate_layout_requested_) {
        recreate_layout_requested_ = false;
        has_damage_ = true;
 
        frame_buffer_.set_size(get_rectangle().size);
        frame_buffer_.ensure(ctx);
 
        content_canvas.set_resolution(ctx, get_rectangle().size);
        overlay_canvas.set_resolution(ctx, get_viewport_size());
        return true;
    }
    return false;
}
 
void canvas_overlay::post_recreate_layout() {
    recreate_layout_requested_ = true;
}
 
void canvas_overlay::clear_damage() {
    has_damage_ = false;
}
 
bool canvas_overlay::is_damaged() const {
    return has_damage_;
}
 
void canvas_overlay::begin_content(context& ctx, bool clear_frame_buffer) {
 
    frame_buffer_.enable(ctx);
    if(clear_frame_buffer) {
        ctx.push_bg_color();
        ctx.set_bg_color({ 0.0f, 0.0f, 0.0f, 1.0f });
        ctx.clear_background(true, false);
        ctx.pop_bg_color();
    }
}
 
void canvas_overlay::end_content(context& ctx, bool keep_damage) {
 
    frame_buffer_.disable(ctx);
    has_damage_ = keep_damage;
}
 
void canvas_overlay::draw_impl(context& ctx) {
 
    ctx.push_depth_test_state();
    ctx.disable_depth_test();
 
    ctx.push_blend_state();
    const context::BlendState blend_state = {
        true,
        BF_SRC_ALPHA,
        BF_ONE_MINUS_SRC_ALPHA,
        BF_ZERO,
        BF_ONE_MINUS_SRC_ALPHA
    };
    ctx.set_blend_state(blend_state);
 
    
    if(has_damage_)
        draw_content(ctx);
 
    // draw frame buffer texture to screen
    ctx.set_blend_func(BF_ONE, BF_SRC_ALPHA);
 
    overlay_canvas.enable_shader(ctx, "rectangle");
    overlay_canvas.set_style(ctx, blit_style_);
    frame_buffer_.enable_attachment(ctx, "color", 0);
    overlay_canvas.draw_shape(ctx, get_rectangle());
    frame_buffer_.disable_attachment(ctx, "color");
    overlay_canvas.disable_current_shader(ctx);
 
    ctx.pop_blend_state();
    ctx.pop_depth_test_state();
}
 
}
}