Step 119: zoom controls

PROGRESS.md

@@ -222,6 +222,7 @@ All 38 steps implemented and passing. Each step has a corresponding test (`step1
 - [x] Step 116: **IMPLEMENTED** — Project save/load (.whetstone) with AST serialization (4/4 tests pass)
 - [x] Step 117: **IMPLEMENTED** — Session persistence (layout, buffers, cursors, folds) (5/5 tests pass)
 - [x] Step 118: **IMPLEMENTED** — Settings panel + persistence (11/11 tests pass)
+- [x] Step 119: **IMPLEMENTED** — Zoom controls and status bar indicator (5/5 tests pass)
 
 ---
 
@@ -323,6 +324,7 @@ vcpkg's imgui 1.91.9 removed the `sdl2-binding` feature (only `sdl3-binding` exi
 **Step 116:** Compile and pass (4/4)
 **Step 117:** Compile and pass (5/5)
 **Step 118:** Compile and pass (11/11)
+**Step 119:** Compile and pass (5/5)
 
 ---
 
@@ -374,7 +376,7 @@ vcpkg's imgui 1.91.9 removed the `sdl2-binding` feature (only `sdl3-binding` exi
 
 ## What's Next
 
-Sprint 4 in progress. Step 118 (settings panel) done. Next: Step 119 (zoom).
+Sprint 4 in progress. Step 119 (zoom) done. Next: Step 120 (undo/redo rework).
 
 ---
 
@@ -454,3 +456,4 @@ Sprint 4 in progress. Step 118 (settings panel) done. Next: Step 119 (zoom).
 | 2026-02-09 | Codex | Step 116: Project save/load (.whetstone) with AST serialization. 4/4 tests pass. |
 | 2026-02-09 | Codex | Step 117: Session persistence (layout, buffers, cursors, folds). 5/5 tests pass. |
 | 2026-02-09 | Codex | Step 118: Settings panel + persistence. 11/11 tests pass. |
+| 2026-02-09 | Codex | Step 119: Zoom controls and status bar indicator. 5/5 tests pass. |

editor/CMakeLists.txt

@@ -634,6 +634,10 @@ add_executable(step118_test tests/step118_test.cpp)
 target_include_directories(step118_test PRIVATE src)
 target_link_libraries(step118_test PRIVATE nlohmann_json::nlohmann_json)
 
+add_executable(step119_test tests/step119_test.cpp)
+target_include_directories(step119_test PRIVATE src)
+target_link_libraries(step119_test PRIVATE nlohmann_json::nlohmann_json)
+
 find_package(SDL2 CONFIG REQUIRED)
 find_package(OpenGL REQUIRED)
 find_package(glad CONFIG REQUIRED)

editor/src/ZoomUtils.h

@@ -0,0 +1,14 @@
+#pragma once
+// Step 119: Zoom utilities
+
+inline int clampFontSize(int size, int minSize = 12, int maxSize = 24) {
+    if (size < minSize) return minSize;
+    if (size > maxSize) return maxSize;
+    return size;
+}
+
+inline int zoomPercent(int fontSize, float baseFontSize) {
+    if (baseFontSize <= 0.0f) return 100;
+    float pct = (fontSize / baseFontSize) * 100.0f;
+    return (int)(pct + 0.5f);
+}

editor/src/main.cpp

@@ -48,6 +48,7 @@
 #include "Orchestrator.h"
 #include "ProjectManager.h"
 #include "SessionManager.h"
+#include "ZoomUtils.h"
 #include "ast/Serialization.h"
 #include "ast/Generator.h"
 #include "ast/Annotation.h"
@@ -1962,6 +1963,17 @@ int main(int, char**) {
                     state.commandSelected = 0;
                 }
 
+                auto applyFontSize = [&](int newSize) {
+                    newSize = clampFontSize(newSize);
+                    state.settings.setFontSize(newSize);
+                    io.FontGlobalScale = newSize / baseFontSize;
+                    state.saveSettingsToDisk();
+                };
+
+                if ((sdlMod & KMOD_CTRL) && sym == SDLK_0) {
+                    applyFontSize((int)baseFontSize);
+                }
+
                 if (key != 0 && mods != WMOD_NONE) {
                     KeyCombo combo{key, mods};
                     std::string action = state.keys.getAction(combo);
@@ -1979,6 +1991,8 @@ int main(int, char**) {
                         std::string lang = state.active() ? state.active()->language : "python";
                         state.createBuffer(state.makeUntitledName(), "", lang);
                     }
+                    else if (action == "view.zoomIn")  applyFontSize(state.settings.getFontSize() + 1);
+                    else if (action == "view.zoomOut") applyFontSize(state.settings.getFontSize() - 1);
                 }
             }
         }
@@ -4009,6 +4023,10 @@ int main(int, char**) {
             ImGui::Text("Keys: %s", KeybindingManager::profileName(state.keys.getProfile()));
             ImGui::SameLine(0, 30);
 
+            // Zoom
+            ImGui::Text("Zoom: %d%%", zoomPercent(state.settings.getFontSize(), baseFontSize));
+            ImGui::SameLine(0, 30);
+
             // Modified indicator
             if (state.active() && state.active()->modified)
                 ImGui::Text("Modified");

editor/tests/step119_test.cpp

@@ -0,0 +1,27 @@
+// Step 119 TDD Test: Zoom utilities
+#include "ZoomUtils.h"
+#include <iostream>
+
+static void expect(bool cond, const std::string& name, int& passed, int& failed) {
+    if (cond) {
+        std::cout << "Test " << (passed + failed + 1) << " PASS: " << name << "\n";
+        ++passed;
+    } else {
+        std::cout << "Test " << (passed + failed + 1) << " FAIL: " << name << "\n";
+        ++failed;
+    }
+}
+
+int main() {
+    int passed = 0;
+    int failed = 0;
+
+    expect(clampFontSize(10) == 12, "clamp low", passed, failed);
+    expect(clampFontSize(30) == 24, "clamp high", passed, failed);
+    expect(clampFontSize(18) == 18, "clamp ok", passed, failed);
+    expect(zoomPercent(15, 15.0f) == 100, "zoom 100", passed, failed);
+    expect(zoomPercent(18, 15.0f) == 120, "zoom 120", passed, failed);
+
+    std::cout << "\n=== Step 119 Results: " << passed << " passed, " << failed << " failed ===\n";
+    return failed == 0 ? 0 : 1;
+}

sprint4_plan.md

@@ -380,7 +380,7 @@ AST extensions for Sprint 5.
   keybinding profile. Persisted to `~/.whetstone/settings.json`.
   *New:* `SettingsManager.h`
 
-- [ ] **Step 119: Zoom**
+- [x] **Step 119: Zoom**
   Ctrl+= zoom in, Ctrl+- zoom out, Ctrl+0 reset. Scales the editor font
   size dynamically. Status bar shows current zoom level.
   *Modifies:* `main.cpp`