From a9c8b6797557cdfa1f8a5afde8b59ca47822371a Mon Sep 17 00:00:00 2001
From: Bruno <bruno.herbelin@gmail.com>
Date: Fri, 6 Aug 2021 13:23:59 +0200
Subject: [PATCH] Implementation of custom Masks

FrameBuffer accepts to fill any size of FrameBufferImage as input, and a Dialog in TextureView allows to select a JPG or PNG.
---
 FrameBuffer.cpp | 54 ++++++++++++++++++++++++++++++++++++++++---------
 FrameBuffer.h   |  1 +
 TextureView.cpp | 16 +++++++++++++++
 3 files changed, 62 insertions(+), 9 deletions(-)

diff --git a/FrameBuffer.cpp b/FrameBuffer.cpp
index f1af503..61939d0 100644
--- a/FrameBuffer.cpp
+++ b/FrameBuffer.cpp
@@ -342,7 +342,16 @@ FrameBufferImage::FrameBufferImage(jpegBuffer jpgimg) :
         rgb = stbi_load_from_memory(jpgimg.buffer, jpgimg.len, &width, &height, &c, 3);
 }
 
-FrameBufferImage::~FrameBufferImage() {
+FrameBufferImage::FrameBufferImage(const std::string &filename) :
+    rgb(nullptr), width(0), height(0)
+{
+    int c = 0;
+    if (!filename.empty())
+        rgb = stbi_load(filename.c_str(), &width, &height, &c, 3);
+}
+
+FrameBufferImage::~FrameBufferImage()
+{
     if (rgb!=nullptr)
         delete rgb;
 }
@@ -392,22 +401,49 @@ bool FrameBuffer::fill(FrameBufferImage *image)
     if (!framebufferid_)
         init();
 
-    // not compatible for RGB
+    // only compatible for RGB FrameBuffers
     if (use_alpha_ || use_multi_sampling_)
         return false;
 
     // invalid image
     if ( image == nullptr ||
          image->rgb==nullptr ||
-         image->width !=attrib_.viewport.x ||
-         image->height!=attrib_.viewport.y )
+         image->width < 1 ||
+         image->height < 1 )
         return false;
 
-    // fill texture with image
-    glBindTexture(GL_TEXTURE_2D, textureid_);
-    glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, image->width, image->height,
-                    GL_RGB, GL_UNSIGNED_BYTE, image->rgb);    
-    glBindTexture(GL_TEXTURE_2D, 0);
+    // is it same size ?
+    if (image->width == attrib_.viewport.x && image->height == attrib_.viewport.y ) {
+        // directly fill texture with image
+        glBindTexture(GL_TEXTURE_2D, textureid_);
+        glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, image->width, image->height,
+                        GL_RGB, GL_UNSIGNED_BYTE, image->rgb);
+        glBindTexture(GL_TEXTURE_2D, 0);
+    }
+    else {
+        uint textureimage, framebufferimage;
+        // generate texture
+        glGenTextures(1, &textureimage);
+        glBindTexture(GL_TEXTURE_2D, textureimage);
+        glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB8, image->width, image->height, 0, GL_RGB, GL_UNSIGNED_BYTE, image->rgb);
+        glBindTexture(GL_TEXTURE_2D, 0);
+
+        // create a framebuffer object
+        glGenFramebuffers(1, &framebufferimage);
+        glBindFramebuffer(GL_FRAMEBUFFER, framebufferimage);
+        glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, textureimage, 0);
+
+        // blit to the frame buffer object with interpolation
+        glBindFramebuffer(GL_READ_FRAMEBUFFER, framebufferimage);
+        glBindFramebuffer(GL_DRAW_FRAMEBUFFER, framebufferid_);
+        glBlitFramebuffer(0, 0, image->width, image->height,
+                          0, 0, attrib_.viewport.x, attrib_.viewport.y, GL_COLOR_BUFFER_BIT, GL_LINEAR);
+        glBindFramebuffer(GL_FRAMEBUFFER, 0);
+
+        // cleanup
+        glDeleteFramebuffers(1, &framebufferimage);
+        glDeleteTextures(1, &textureimage);
+    }
 
     return true;
 }
diff --git a/FrameBuffer.h b/FrameBuffer.h
index 5caf8a1..554b735 100644
--- a/FrameBuffer.h
+++ b/FrameBuffer.h
@@ -24,6 +24,7 @@ public:
 
     FrameBufferImage(int w, int h);
     FrameBufferImage(jpegBuffer jpgimg);
+    FrameBufferImage(const std::string &filename);
     // non assignable class
     FrameBufferImage(FrameBufferImage const&) = delete;
     FrameBufferImage& operator=(FrameBufferImage const&) = delete;
diff --git a/TextureView.cpp b/TextureView.cpp
index a52396e..9a2126b 100644
--- a/TextureView.cpp
+++ b/TextureView.cpp
@@ -22,6 +22,7 @@
 #include "Decorations.h"
 #include "UserInterfaceManager.h"
 #include "ActionManager.h"
+#include "DialogToolkit.h"
 #include "Log.h"
 
 #include "TextureView.h"
@@ -717,6 +718,21 @@ void TextureView::draw()
                         ImGui::EndPopup();
                     }
 
+                    static DialogToolkit::OpenImageDialog maskdialog("Select Image");
+
+                    ImGui::SameLine();
+                    if (ImGui::Button(ICON_FA_FOLDER_OPEN))
+                        maskdialog.open();
+                    if (maskdialog.closed() && !maskdialog.path().empty())
+                    {
+                        FrameBufferImage *img = new FrameBufferImage(maskdialog.path());
+                        if (edit_source_->maskbuffer_->fill( img )) {
+                            std::ostringstream oss;
+                            oss << edit_source_->name();
+                            oss << ": Mask fill with " << maskdialog.path();
+                            Action::manager().store(oss.str());
+                        }
+                    }
 
                 }
                 // disabled info