buffer_image.cpp

#include <iostream>
#include <algorithm>
#include "glviewer.h"
#include "buffer_image.h"
using namespace std;
using namespace MaxLib;


namespace GLViewer {

// Global counter for buffer
static uint m_Counter_ImageID = 0;


RenderableImage::RenderableImage(Viewer* viewer, ImageTexture texture, const glm::vec2& position2d, const glm::vec2& size, const glm::vec4& colour)
    : m_Texture(texture), m_Position(position2d), m_Size(size), m_Colour(colour), m_Valid(true)
{
    (void)viewer;
}

RenderableImage::RenderableImage(Viewer* viewer, ImageTexture texture, const glm::vec3& position3d, const glm::vec2& size, const glm::vec4& colour) 
    : m_Texture(texture), m_Size(size), m_Colour(colour)
{
    // convert world coords to screen coords
    if(std::optional<glm::vec2> screenCoords = viewer->WorldToScreenCoords(position3d)) {
        // top left of image
        m_Position = *screenCoords - (m_Size / 2.0f);
        m_Valid = true;
    }
}
    
void RenderableImage::Render() 
{			  
    if(!m_Valid) { return; }
    // convert colour
    ImU32 colour = ImGui::GetColorU32(ImVec4(m_Colour.r, m_Colour.g, m_Colour.b, m_Colour.a));
    ImVec2 p_min = ImVec2(m_Position.x, m_Position.y);
    ImVec2 p_max = ImVec2(m_Position.x + m_Size.x, m_Position.y + m_Size.y);
    // add to ImGui draw list
    ImGui::GetBackgroundDrawList()->AddImage((void*)(intptr_t)m_Texture.textureID, p_min, p_max, ImVec2(0, 0), ImVec2(1, 1), colour);
}

ImageBuffer::ImageBuffer(Viewer* viewer) 
    : m_Parent(viewer), m_ID(++m_Counter_ImageID)
{}
    
    
void ImageBuffer::Add2DImage(ImageTexture texture, const glm::vec2& position2d, const glm::vec2& size, const glm::vec4& colour) 
{
    m_Images.emplace_back(m_Parent, texture, position2d, size, colour);
}

void ImageBuffer::Add3DImage(ImageTexture texture, const glm::vec3& position3d, const glm::vec2& size, const glm::vec4& colour) 
{
    m_Images.emplace_back(m_Parent, texture, position3d, size, colour);
}


void ImageBuffer::ClearAll() 
{ 
    m_Images.erase(m_Images.begin(), m_Images.end()); 
}

void ImageBuffer::SetData(std::function<void(ImageBuffer&)> cb_AddData)
{   // Clear old data
    ClearAll();
    // Add vertices via callback
    cb_AddData(*this);  
}

void ImageBuffer::Render() 
{
    // add each image to imgui draw list
    for(RenderableImage& image : m_Images) {
        image.Render();        
    } 
}
    
} // End namespace GLViewer