window scrolling

4 files changed, 57 insertions, 22 deletions

diff --git a/platform/desktop/desktop.c b/platform/desktop/desktop.c
index 9574c9c..b156e56 100644
--- a/platform/desktop/desktop.c
+++ b/platform/desktop/desktop.c
@@ -45,6 +45,7 @@ typedef struct {
     GLint uniform_tex_loc;
     GLuint screen_handle;
     uint32_t typed;
+    double scroll;
 } Desktop_Platform;
 
 Desktop_Platform p;
@@ -57,6 +58,15 @@ void character_callback(GLFWwindow *window, unsigned int cp)
 }
 
 static
+void scroll_callback(GLFWwindow* window, double x, double y)
+{
+    (void)window;
+    (void)x;
+    p.scroll = y;
+}
+
+
+static
 GLuint compile_shader(GLenum type, const char *src)
 {
     GLuint shader = glCreateShader(type);
@@ -102,6 +112,7 @@ void ty_platform_init(ty_Ctx *ctx)
         ty_log_fatal(TY_PLATFORM_ERR, "could not load GLAD");
 
     glfwSetCharCallback(p.win, character_callback);
+    glfwSetScrollCallback(p.win, scroll_callback);
 
     ty_Vec2 vertices[] = {
         ty_vec2(-1, -1), ty_vec2(0, 1),
@@ -180,6 +191,8 @@ void ty_platform_deinit(void)
 
 void ty_platform_frame(ty_Image img)
 {
+    p.scroll = 0;
+
     glfwPollEvents();
 
     int win_width, win_height;
@@ -283,3 +296,8 @@ bool ty_platform_get_typed_char(uint32_t *c)
     p.typed = 0;
     return true;
 }
+
+int ty_platform_get_scroll(void)
+{
+    return (int)p.scroll;
+}
diff --git a/teensy/teensy_platform.h b/teensy/teensy_platform.h
index 8a1daa6..419922c 100644
--- a/teensy/teensy_platform.h
+++ b/teensy/teensy_platform.h
@@ -16,5 +16,6 @@ bool ty_platform_is_button_down(ty_Button btn);
 // Optional, no editor if not implemented
 ty_Vec2i ty_platform_get_mouse(void);
 bool ty_platform_get_typed_char(uint32_t *c);
+int ty_platform_get_scroll(void);
 
 #endif // TEENSY_PLATFORM_H_
diff --git a/teensy/teensy_ui.c b/teensy/teensy_ui.c
index 4dd9d5d..5913005 100644
--- a/teensy/teensy_ui.c
+++ b/teensy/teensy_ui.c
@@ -56,11 +56,11 @@ typedef struct {
     Layout layout_stack[MAX_LAYOUTS];
     ty_Recti rect;
     uint32_t flags;
-    bool focused;
     bool lmb_down;
     bool rmb_down;
     bool lmb_pressed;
     bool rmb_pressed;
+    int scroll;
 } Window;
 
 typedef struct {
@@ -77,6 +77,7 @@ typedef struct {
 
     ty_Vec2i prev_mouse_pos;
 
+    Window *focused_win;
     const tyui_Text_Input *focused_text_box;
 } Ctx;
 
@@ -84,6 +85,18 @@ static tyui_Style default_style;
 static Ctx tyui;
 
 static
+ty_Recti win_content(Window *win)
+{
+    ty_Recti rect = win->rect;
+    if (!(win->flags & TYUI_WIN_NOTITLE)) {
+        rect.y += tyui.style.title_bar_height;
+        rect.h -= tyui.style.title_bar_height;
+    }
+
+    return rect;
+}
+
+static
 void rect_cmd(ty_Recti rect, ty_Color color)
 {
     Cmd cmd = {0};
@@ -123,9 +136,9 @@ void clip_cmd(ty_Recti rect)
     cmd.kind = CMD_CLIP;
 
     if (rect.w < 0 || rect.h < 0)
-        rect = window()->rect; // This is a full screen clip
+        rect = win_content(window()); // This is a full screen clip
 
-    cmd.rect = ty_recti_clamp(rect, window()->rect);
+    cmd.rect = ty_recti_clamp(rect, win_content(window()));
     ty_list_append(&window()->cmds, cmd);
 }
 
@@ -214,18 +227,6 @@ bool is_hovered(ty_Recti rect)
 }
 
 static
-ty_Recti win_rect(Window *win)
-{
-    ty_Recti rect = win->rect;
-    if (!(win->flags & TYUI_WIN_NOTITLE)) {
-        rect.y += tyui.style.title_bar_height;
-        rect.h -= tyui.style.title_bar_height;
-    }
-
-    return rect;
-}
-
-static
 Window create_window(ty_Recti rect, uint32_t flags)
 {
     Window win = {0};
@@ -263,7 +264,9 @@ void tyui_init(const ty_Font *font)
     root_flags |= TYUI_WIN_NORESIZEY;
     root_flags |= TYUI_WIN_NOCLOSE;
     root_flags |= TYUI_WIN_NOMOVE;
+    root_flags |= TYUI_WIN_NOTITLE;
     root_flags |= TYUI_WIN_INVISIBLE;
+    root_flags |= TYUI_WIN_ALWAYS_BELOW;
 
     tyui.root = create_window(
         ty_recti(0, 0, ctx.hints.scr_width, ctx.hints.scr_height),
@@ -325,6 +328,8 @@ bool tyui_begin_window_ex(tyui_Window_Conf conf, bool *closed_ptr)
     assert(conf.title);
     assert(conf.id);
 
+    tyui.active = &tyui.root;
+
     bool closed = false;
 
     if (closed_ptr)
@@ -345,7 +350,6 @@ bool tyui_begin_window_ex(tyui_Window_Conf conf, bool *closed_ptr)
     }
 
     Window *win = &tyui.windows[*conf.id - 1];
-    tyui.active = win;
     win->layout = win->layout_stack;
 
     ty_Vec2i mouse_pos = ty_mouse_pos();
@@ -415,7 +419,7 @@ bool tyui_begin_window_ex(tyui_Window_Conf conf, bool *closed_ptr)
     if (win->flags & TYUI_WIN_INVISIBLE)
         goto skip_invisible;
 
-    ty_Recti body_rect = win_rect(win);
+    ty_Recti body_rect = win_content(win);
     rect_cmd(body_rect, tyui.style.win_border);
     rect_cmd(ty_recti_shrink(body_rect, 1), tyui.style.win_bg);
 
@@ -437,8 +441,19 @@ bool tyui_begin_window_ex(tyui_Window_Conf conf, bool *closed_ptr)
 
 skip_invisible:
 
+    tyui.active = win;
+    clip_cmd(win_content(win));
+
+    // TODO: Maybe make a distinction between focused and the top-most hovered
+    // window? By forcing the user to focus the window, they must click on it
+    // beforehand, which is bad UX.
+    if (tyui.focused_win == win && is_hovered(win->rect)) {
+        win->scroll += ty_platform_get_scroll() * TYUI_SCROLL;
+        win->scroll = ty_min(win->scroll, 0);
+    }
+
     tyui_push_layout((float[]){-1, 0});
-    layout()->total_height = tyui.style.padding;
+    layout()->total_height = tyui.style.padding + win->scroll;
     if ((win->flags & TYUI_WIN_NOTITLE) == 0)
         layout()->total_height += tyui.style.title_bar_height;
 
@@ -452,9 +467,9 @@ void tyui_end_window(void)
         return;
     }
 
-    clip_cmd(TY_CLIP_NONE);
-
     tyui.active = &tyui.root;
+
+    clip_cmd(window()->rect);
 }
 
 void tyui_text_ex(tyui_Align align, const char *fmt, ...)
@@ -647,7 +662,7 @@ void focus_window(tyui_Id win_id)
         ty_log_err("uh oh");
 
     Window *win = &tyui.windows[win_id - 1];
-    win->focused = true;
+    tyui.focused_win = win;
     if (win->flags & TYUI_WIN_ALWAYS_BELOW)
         return;
 
@@ -665,7 +680,6 @@ void update_windows(void)
         win->rmb_down = false;
         win->lmb_pressed = false;
         win->rmb_pressed = false;
-        win->focused = false;
     }
 
     for (int i = tyui.window_count - 1; i >= 0; i--) {
diff --git a/teensy/teensy_ui.h b/teensy/teensy_ui.h
index c1081d4..237d140 100644
--- a/teensy/teensy_ui.h
+++ b/teensy/teensy_ui.h
@@ -15,6 +15,8 @@
 #define TYUI_WIN_INVISIBLE    (1 << 5)
 #define TYUI_WIN_ALWAYS_BELOW (1 << 6)
 
+#define TYUI_SCROLL (7)
+
 // Marks the beginning of a window, with sane defaults.
 #define tyui_begin_window(_title, _rect, _id, ...) \
     tyui_begin_window_ex((tyui_Window_Conf){ \