cropping ui partly done (upper left cropper works)

src/send_image_popup.cpp

@@ -33,6 +33,8 @@ void SendImagePopup::reset(void) {
 		_tu.destroy(tex_id);
 	}
 	preview_image = {};
+
+	cropping = false;
 }
 
 bool SendImagePopup::load(void) {
@@ -269,18 +271,127 @@ void SendImagePopup::render(void) {
 				height = max_height;
 			}
 
-			// save curser pos
+			// TODO: propergate texture id type
-			// TODO: propergate type
-			ImGui::Image(
-				preview_image.getID<void*>(),
-				ImVec2{static_cast<float>(width), static_cast<float>(height)}
-			);
 
-			// TODO: crop input here
+			// save curser pos
+
+			const auto pre_img_curser_screen = ImGui::GetCursorScreenPos();
+			const auto pre_img_curser = ImGui::GetCursorPos();
+
+			if (cropping) { // if cropping
+				// display full image
+				ImGui::Image(
+					preview_image.getID<void*>(),
+					ImVec2{static_cast<float>(width), static_cast<float>(height)}
+				);
+				const auto post_img_curser = ImGui::GetCursorPos();
+
+
+				ImGui::PushStyleColor(ImGuiCol_Button, ImVec4{0.5f, 0.5f, 0.5f, 0.2f});
+				ImGui::PushStyleColor(ImGuiCol_ButtonActive, ImVec4{0.5f, 0.5f, 0.5f, 0.4f});
+
+				static Rect crop_before_drag = crop_rect;
+				auto ul_clipper_pos = ImVec2{float(crop_rect.x)/original_image.width, float(crop_rect.y)/original_image.height};
+				{ // crop upper left clipper
+
+					ImGui::SetCursorPos({
+						pre_img_curser.x + ul_clipper_pos.x * width,
+						pre_img_curser.y + ul_clipper_pos.y * height
+					});
+
+					static bool dragging_last_frame = false;
+					ImGui::Button("##ul_clipper", {TEXT_BASE_HEIGHT, TEXT_BASE_HEIGHT});
+					if (ImGui::IsMouseDragging(ImGuiMouseButton_Left)) {
+						if (dragging_last_frame) {
+							auto drag_total = ImGui::GetMouseDragDelta();
+							drag_total.x = (drag_total.x / width) * original_image.width;
+							drag_total.y = (drag_total.y / height) * original_image.height;
+
+							crop_rect.x = std::max<float>(crop_before_drag.x + drag_total.x, 0.01f);
+							crop_rect.y = std::max<float>(crop_before_drag.y + drag_total.y, 0.01f);
+
+							crop_rect.x = std::min<int32_t>(crop_rect.x, original_image.width-2);
+							crop_rect.y = std::min<int32_t>(crop_rect.y, original_image.height-2);
+
+							crop_rect.w = crop_before_drag.w - (crop_rect.x - crop_before_drag.x);
+							crop_rect.h = crop_before_drag.h - (crop_rect.y - crop_before_drag.y);
+						} else {
+							if (ImGui::IsItemActive()) {
+								dragging_last_frame = true;
+								// drag started on button, start drag
+								std::cout << "drag started\n";
+							} else {
+								std::cout << "drag but now ours\n";
+							}
+						}
+					} else if (dragging_last_frame) { // was dragging
+						std::cout << "drag ended\n";
+						dragging_last_frame = false;
+
+						crop_rect = sanitizeCrop(crop_rect, original_image.width, original_image.height);
+
+						crop_before_drag = crop_rect;
+					}
+				}
+
+				// crop lower right clipper
+				auto lr_clipper_pos = ImVec2{float(crop_rect.x+crop_rect.w)/original_image.width, float(crop_rect.y+crop_rect.h)/original_image.height};
+
+				{ // 4 lines delimiting the crop result
+					// x vertical
+					ImGui::GetWindowDrawList()->AddLine(
+						{pre_img_curser_screen.x + ul_clipper_pos.x * width, pre_img_curser_screen.y},
+						{pre_img_curser_screen.x + ul_clipper_pos.x * width, pre_img_curser_screen.y + height},
+						0xffffffff,
+						1.f
+					);
+
+					// y horizontal
+					ImGui::GetWindowDrawList()->AddLine(
+						{pre_img_curser_screen.x,			pre_img_curser_screen.y + ul_clipper_pos.y * height},
+						{pre_img_curser_screen.x + width,	pre_img_curser_screen.y + ul_clipper_pos.y * height},
+						0xffffffff,
+						1.f
+					);
+
+					// w vertical
+					// h horizontal
+				}
+
+				// cancel/ok buttons in the img center?
+
+				ImGui::PopStyleColor(2);
+
+				ImGui::SetCursorPos(post_img_curser);
+
+				crop_rect = sanitizeCrop(crop_rect, original_image.width, original_image.height);
+			} else {
+				crop_rect = sanitizeCrop(crop_rect, original_image.width, original_image.height);
+
+				// display cropped area
+				ImGui::Image(
+					preview_image.getID<void*>(),
+					ImVec2{static_cast<float>(width), static_cast<float>(height)},
+					ImVec2{float(crop_rect.x)/original_image.width, float(crop_rect.y)/original_image.height},
+					ImVec2{float(crop_rect.x+crop_rect.w)/original_image.width, float(crop_rect.y+crop_rect.h)/original_image.height}
+				);
+				const auto post_img_curser = ImGui::GetCursorPos();
+
+				ImGui::SetCursorPos(pre_img_curser);
+
+				// TODO: fancy cropping toggle
+				ImGui::PushStyleColor(ImGuiCol_Button, ImVec4{0.5f, 0.5f, 0.5f, 0.2f});
+				if (ImGui::Button("crop", {TEXT_BASE_WIDTH*8, TEXT_BASE_HEIGHT*2})) {
+					cropping = true;
+				}
+				ImGui::PopStyleColor();
+
+				ImGui::SetCursorPos(post_img_curser);
+			}
 		}
 
-		crop_rect = sanitizeCrop(crop_rect, original_image.width, original_image.height);
 		const bool cropped = crop_rect.x != 0 || crop_rect.y != 0 || crop_rect.w != original_image.width || crop_rect.h != original_image.height;
+		ImGui::Text("crop: x:%d y:%d w:%d h:%d", crop_rect.x, crop_rect.y, crop_rect.w, crop_rect.h);
 
 		bool recalc_size = false;
 		if (cropped) {

src/send_image_popup.hpp

@@ -22,14 +22,16 @@ struct SendImagePopup {
 	ImageLoaderI::ImageResult original_image;
 
 	struct Rect {
-		uint32_t x {0};
+		int32_t x {0};
-		uint32_t y {0};
+		int32_t y {0};
 
-		uint32_t w {0};
+		int32_t w {0};
-		uint32_t h {0};
+		int32_t h {0};
 	};
 	Rect crop_rect;
 
+	bool cropping {false};
+
 	// texture to render (orig img)
 	TextureEntry preview_image;