margin, scroll, richtextHEADmaster

3 files changed, 304 insertions, 66 deletions

diff --git a/src/mgui/mgui.c b/src/mgui/mgui.c
index 0d9f20d..fdb4cb4 100644
--- a/src/mgui/mgui.c
+++ b/src/mgui/mgui.c
@@ -8,13 +8,13 @@ static mgl_vec2i root_widget_size;
 static mgl_clock global_timer;
 static double frame_time;
 
-void mgui_init() {
+void mgui_init(void) {
     mgl_clock_init(&global_timer);
     mgui_async_image_init();
     frame_time = 0.0;
 }
 
-void mgui_deinit() {
+void mgui_deinit(void) {
     mgui_async_image_deinit();
 }
 
@@ -35,13 +35,13 @@ void mgui_draw(mgui_widget *root_widget, mgl_window *window) {
         frame_time = 1.0;
 }
 
-double mgui_get_seconds_since_last_update() {
+double mgui_get_seconds_since_last_update(void) {
     double elapsed_time_sec = mgl_clock_get_elapsed_time_seconds(&global_timer);
     if(elapsed_time_sec > 1.0)
         elapsed_time_sec = 1.0;
     return elapsed_time_sec;
 }
 
-double mgui_get_frame_time_seconds() {
+double mgui_get_frame_time_seconds(void) {
     return frame_time;
 }
diff --git a/src/mgui/richtext.c b/src/mgui/richtext.c
index 77ee3c1..8de067f 100644
--- a/src/mgui/richtext.c
+++ b/src/mgui/richtext.c
@@ -4,21 +4,46 @@
 #include "../../include/alloc.h"
 #include <mgl/mgl.h>
 #include <mgl/window/event.h>
+#include <mgl/window/window.h>
 #include <mgl/graphics/vertex.h>
 #include <mgl/graphics/font.h>
 #include <mgl/graphics/texture.h>
+#include <mgl/graphics/rectangle.h>
 #include <mgl/system/utf8.h>
 #include <string.h>
 #include <assert.h>
 
 #define TAB_WIDTH 4
+
 #define LATIN_INDEX 0
 #define CJK_INDEX 1
 #define NUM_VERTEX_DATA 2
 
+typedef enum {
+    MGUI_RICHTEXT_SIDE_LEFT,
+    MGUI_RICHTEXT_SIDE_RIGHT
+} mgui_richtext_selection_side;
+
+typedef struct {
+    size_t start_vertex_data_index;
+    size_t start_vertex_index;
+    mgui_richtext_selection_side start_side;
+
+    size_t current_vertex_data_index;
+    size_t current_vertex_index;
+    mgui_richtext_selection_side current_side;
+
+    bool selecting_text;
+    mgui_richtext *selecting_widget;
+} mgui_richtext_selection;
+
+static mgui_richtext_selection selection = {0};
+
 /* TODO: Scale richtext by scale setting */
 /* TODO: Split multiple lines into multiple vertex draw calls and do not render the vertices outside the scissor */
+/*     Maybe make the rows global and add the visible text into the rows */
 /* TODO: Cleanup vertex when deleting mgui_richtext widget */
+/* TODO: Use global vertex buffers instead of mgl_vertices_draw. The global vertex buffers should only exist for the visible text items */
 
 static int round_float(float value) {
     return value + 0.5f;
@@ -32,6 +57,10 @@ static int min_int(int a, int b) {
     return a <= b ? a : b;
 }
 
+static int abs_int(int value) {
+    return value >= 0 ? value : -value;
+}
+
 /* TODO: Is there a more efficient way to do this? maybe japanese characters have a specific bit-pattern? */
 static bool is_japanese_codepoint(uint32_t codepoint) {
     return (codepoint >= 0x2E80 && codepoint <= 0x2FD5)     /* Kanji radicals */
@@ -54,13 +83,13 @@ static bool is_korean_codepoint(uint32_t codepoint) {
 
 /* TODO: Is there a more efficient way to do this? maybe chinese characters have a specific bit-pattern? */
 static bool is_chinese_codepoint(uint32_t codepoint) {
-    return (codepoint >= 0x4E00 && codepoint <= 0x9FFF)     /* CJK Unified Ideographs */
-        || (codepoint >= 0x3400 && codepoint <= 0x4DBF)     /* CJK Unified Ideographs Extension A */
+    return (codepoint >= 0x4E00  && codepoint <= 0x9FFF)    /* CJK Unified Ideographs */
+        || (codepoint >= 0x3400  && codepoint <= 0x4DBF)    /* CJK Unified Ideographs Extension A */
         || (codepoint >= 0x20000 && codepoint <= 0x2A6DF)   /* CJK Unified Ideographs Extension B */
         || (codepoint >= 0x2A700 && codepoint <= 0x2B73F)   /* CJK Unified Ideographs Extension C */
         || (codepoint >= 0x2B740 && codepoint <= 0x2B81F)   /* CJK Unified Ideographs Extension D */
         || (codepoint >= 0x2B820 && codepoint <= 0x2CEAF)   /* CJK Unified Ideographs Extension E */
-        || (codepoint >= 0xF900 && codepoint <= 0xFAFF)     /* CJK Compatibility Ideographs */
+        || (codepoint >= 0xF900  && codepoint <= 0xFAFF)    /* CJK Compatibility Ideographs */
         || (codepoint >= 0x2F800 && codepoint <= 0x2FA1F);  /* CJK Compatibility Ideographs Supplement */
 }    
 
@@ -129,6 +158,11 @@ mgui_richtext* mgui_richtext_create(const char *str, size_t size, unsigned char
 }
 
 void mgui_richtext_destroy(mgui_richtext *richtext) {
+    if(selection.selecting_widget == richtext) {
+        selection.selecting_text = false;
+        selection.selecting_widget = NULL;
+    }
+
     for(size_t i = 0; i < NUM_VERTEX_DATA; ++i) {
         mgui_free(richtext->vertex_data[i].vertices);
     }
@@ -271,11 +305,159 @@ void mgui_richtext_calculate_size(mgui_richtext *self, mgl_vec2i max_size) {
     }
 }
 
+static bool get_first_vertex_index(mgui_richtext *self, size_t *vertex_data_index, size_t *vertex_index) {
+    for(size_t j = 0; j < NUM_VERTEX_DATA; ++j) {
+        mgui_richtext_vertex_data *vertex_data = &self->vertex_data[j];
+        if(vertex_data->vertex_count > 0) {
+            *vertex_data_index = j;
+            *vertex_index = 0;
+            return true;
+        }
+    }
+    return false;
+}
+
+static bool get_last_vertex_index(mgui_richtext *self, size_t *vertex_data_index, size_t *vertex_index) {
+    for(size_t j = 0; j < NUM_VERTEX_DATA; ++j) {
+        mgui_richtext_vertex_data *vertex_data = &self->vertex_data[j];
+        if(vertex_data->vertex_count > 0) {
+            *vertex_data_index = j;
+            *vertex_index = vertex_data->vertex_count - 6;
+            return true;
+        }
+    }
+    return false;
+}
+
+/* TODO: For the start record the coordinate. Then for the current take the row closest to the cursor and then the column */
+/*    Clamp to text bounding box */
+static bool mgui_richtext_get_closest_vertex_to_point(mgui_richtext *self, mgl_vec2f pos, size_t *vertex_data_index, size_t *vertex_index, mgui_richtext_selection_side *side) {
+    if(pos.x < self->position.x) {
+        if(!get_first_vertex_index(self, vertex_data_index, vertex_index))
+            return false;
+        *side = MGUI_RICHTEXT_SIDE_LEFT;
+    }
+
+    // TODO: BLALBLA SIDES
+
+    if(pos.x > self->position.x + self->render_size.x) {
+        if(!get_last_vertex_index(self, vertex_data_index, vertex_index))
+            return false;
+        *side = MGUI_RICHTEXT_SIDE_LEFT;
+    }
+
+    if(pos.x < self->position.x || pos.x > self->position.x + self->render_size.x)
+        return false;
+
+    if(pos.y < self->position.y || pos.y > self->position.y + self->render_size.y)
+        return false;
+
+    /* TODO: Binary search, and when moving cursor make binary search relative to the vertex that was closest to the cursor the last time */
+    /* TODO: Get closest vertex instead of the vertex which the point is inside (make sure bounds are properly checked, for example the first row might be less than render_size.x in width) */
+    for(size_t j = 0; j < NUM_VERTEX_DATA; ++j) {
+        mgui_richtext_vertex_data *vertex_data = &self->vertex_data[j];
+        for(size_t i = 0; i < vertex_data->vertex_count; i += 6) {
+            mgl_vertex *top_left_vertex = &vertex_data->vertices[i + 1];
+            mgl_vertex *bottom_right_vertex = &vertex_data->vertices[i + 4];
+            mgl_vec2f vertex_pos = (mgl_vec2f){ self->position.x + top_left_vertex->position.x, self->position.y + top_left_vertex->position.y };
+            mgl_vec2f vertex_size = (mgl_vec2f){ bottom_right_vertex->position.x - top_left_vertex->position.x, bottom_right_vertex->position.y - top_left_vertex->position.y };
+            if(mgui_rectangle_contains(vertex_pos, vertex_size, pos)) {
+                *vertex_data_index = j;
+                *vertex_index = i;
+                *side = pos.x - vertex_pos.x < vertex_size.x * 0.5f ? MGUI_RICHTEXT_SIDE_LEFT : MGUI_RICHTEXT_SIDE_RIGHT;
+                return true;
+            }
+        }
+    }
+
+    return false;
+}
+
+// TODO: Text selection in draw
+
 void mgui_richtext_on_event(mgui_richtext *self, mgl_window *window, mgl_event *event) {
-    /* TODO: Implement */
-    (void)self;
     (void)window;
-    (void)event;
+
+    /* TODO: Reset text selection if text content is modified or if the text is modified in any other way (text size changed or anything else that affects text position or size) */
+    if(event->type == MGL_EVENT_MOUSE_BUTTON_PRESSED && event->mouse_button.button == MGL_BUTTON_LEFT && !selection.selecting_text) {
+        mgl_vec2f mouse_pos = (mgl_vec2f){ event->mouse_button.x, event->mouse_button.y };
+        if(!mgui_richtext_get_closest_vertex_to_point(self, mouse_pos, &selection.start_vertex_data_index, &selection.start_vertex_index, &selection.start_side))
+        {
+            selection.selecting_text = false;
+            selection.selecting_widget = NULL;
+            return;
+        }
+
+        selection.selecting_text = true;
+        selection.selecting_widget = self;
+
+        selection.current_vertex_data_index = selection.start_vertex_data_index;
+        selection.current_vertex_index = selection.start_vertex_index;
+        selection.current_side = selection.start_side;
+    } else if(event->type == MGL_EVENT_MOUSE_BUTTON_RELEASED && event->mouse_button.button == MGL_BUTTON_LEFT && selection.selecting_widget == self) {
+        selection.selecting_text = false;
+    } else if(event->type == MGL_EVENT_MOUSE_MOVED && selection.selecting_text && selection.selecting_widget == self) {
+        /* TODO: */
+    } else if(event->type == MGL_EVENT_KEY_PRESSED && event->key.code == MGL_KEY_C && event->key.control && selection.selecting_widget == self) {
+        /* TODO: Get selected vertices text and copy to clipboard */
+        /*mgl_window_set_clipboard(window, "hello world", 11);*/
+    }
+}
+
+/* Returns -1 if invalid index */
+static int mgui_richtext_get_line_from_vertex(mgui_richtext *self, size_t vertex_data_index, size_t vertex_index) {
+    if(self->character_size == 0)
+        return -1;
+
+    if(vertex_data_index > NUM_VERTEX_DATA)
+        return -1;
+
+    if(vertex_index > self->vertex_data[vertex_data_index].vertex_count)
+        return -1;
+
+    mgui_richtext_vertex_data *vertex_data = &self->vertex_data[vertex_data_index];
+    mgl_vertex *top_left_vertex = &vertex_data->vertices[vertex_index + 1];
+    return top_left_vertex->position.y / self->character_size;
+}
+
+static mgl_vec2f selection_get_position(mgui_richtext *self, size_t vertex_data_index, size_t vertex_index, mgui_richtext_selection_side side) {
+    mgl_vertex *vertex = &self->vertex_data[vertex_data_index].vertices[vertex_index + (side == MGUI_RICHTEXT_SIDE_LEFT ? 1 : 0)];
+    return vertex->position;
+}
+
+static void mgui_richtext_draw_selection_background(mgui_richtext *self, mgl_window *window) {
+    (void)window;
+    const int start_row = mgui_richtext_get_line_from_vertex(self, selection.start_vertex_data_index, selection.start_vertex_index);
+    const int current_row = mgui_richtext_get_line_from_vertex(self, selection.current_vertex_data_index, selection.current_vertex_index);
+    if(start_row == -1 || current_row == -1)
+        return;
+
+    mgl_rectangle rect = {
+        .position = { 0.0f, 0.0f },
+        .size = { 0.0f, self->character_size },
+        .color = { 60, 60, 180, 255 }
+    };
+
+    if(start_row == current_row) {
+        const mgl_vec2f start_pos = selection_get_position(self, selection.start_vertex_data_index, selection.start_vertex_index, selection.start_side);
+        const mgl_vec2f current_pos = selection_get_position(self, selection.current_vertex_data_index, selection.current_vertex_index, selection.current_side);
+
+        rect.position.x = self->position.x + min_int(start_pos.x, current_pos.x);
+        rect.position.y = self->position.y + (start_row * self->character_size);
+        rect.size.x = abs_int(current_pos.x - start_pos.x);
+        mgl_rectangle_draw(mgl_get_context(), &rect);
+        return;
+    }
+
+    const int y1 = min_int(start_row, current_row);
+    const int y2 = max_int(start_row, current_row);
+    /* TODO: Optimize rendering */
+    for(int i = y1; i < y2; ++i) {
+        rect.position.x = self->position.x;
+        rect.position.y = self->position.y + (i * self->character_size);
+        rect.size.x = self->render_size.x;
+        mgl_rectangle_draw(mgl_get_context(), &rect);
+    }
 }
 
 void mgui_richtext_draw(mgui_richtext *self, mgl_window *window) {
@@ -291,6 +473,15 @@ void mgui_richtext_draw(mgui_richtext *self, mgl_window *window) {
             MGUI_FONT_CJK
         };
 
+        if(selection.selecting_widget == self) {
+            /* TODO: Only if moved */
+            mgl_vec2f mouse_pos = (mgl_vec2f){ window->cursor_position.x, window->cursor_position.y };
+            if(selection.selecting_text) {
+                mgui_richtext_get_closest_vertex_to_point(self, mouse_pos, &selection.current_vertex_data_index, &selection.current_vertex_index, &selection.current_side);
+            }
+            mgui_richtext_draw_selection_background(self, window);
+        }
+
         for(size_t i = 0; i < NUM_VERTEX_DATA; ++i) {
             if(self->vertex_data[i].vertex_count == 0)
                 continue;
diff --git a/src/mgui/scrollview.c b/src/mgui/scrollview.c
index a11862f..5cb4773 100644
--- a/src/mgui/scrollview.c
+++ b/src/mgui/scrollview.c
@@ -1,12 +1,14 @@
 #include "../../include/mgui/scrollview.h"
 #include "../../include/mgui/mgui.h"
 #include "../../include/alloc.h"
+#include "../../include/common.h"
 #include <mgl/mgl.h>
 #include <mgl/window/window.h>
 #include <mgl/window/event.h>
 #include <mgl/graphics/rectangle.h>
 #include <limits.h>
 #include <assert.h>
+#include <stdio.h>
 
 #define SCROLL_ACCEL 20.0f
 #define SCROLL_DEACCEL 10.0f
@@ -29,13 +31,17 @@ static float abs_float(float value) {
     return value >= 0.0f ? value : -value;
 }
 
-mgui_scrollview* mgui_scrollview_create() {
+mgui_scrollview* mgui_scrollview_create(void) {
     mgui_scrollview *scrollview = mgui_alloc(sizeof(mgui_scrollview));
     mgui_widget_init(&scrollview->widget, MGUI_WIDGET_SCROLLVIEW);
     scrollview->child = NULL;
     scrollview->position = (mgl_vec2i){ 0, 0 };
     scrollview->scroll = (mgl_vec2i){ 0, 0 };
     scrollview->mouse_scroll = (mgl_vec2f){ 0.0f, 0.0f };
+    scrollview->scrollbar_pos = (mgl_vec2f){ 0.0f, 0.0f };
+    scrollview->scrollbar_size = (mgl_vec2f){ 0.0f, 0.0f };
+    scrollview->scrollbar_move_prev_pos = (mgl_vec2f){ 0.0f, 0.0f };
+    scrollview->moving_scrollbar = false;
     return scrollview;
 }
 
@@ -84,33 +90,77 @@ void mgui_scrollview_on_event(mgui_scrollview *self, mgl_window *window, mgl_eve
     /* TODO: Allow keyboard navigation if scrollview has focus */
     if(event->type == MGL_EVENT_MOUSE_WHEEL_SCROLLED)
         self->mouse_scroll.y += (event->mouse_wheel_scroll.delta * SCROLL_ACCEL);
+    
+    if(event->type == MGL_EVENT_MOUSE_BUTTON_PRESSED
+        && event->mouse_button.button == MGL_BUTTON_LEFT
+        && mgui_rectangle_contains(self->scrollbar_pos, self->scrollbar_size, (mgl_vec2f){ event->mouse_button.x, event->mouse_button.y }))
+    {
+        self->moving_scrollbar = true;
+        self->scrollbar_move_prev_pos = (mgl_vec2f){ event->mouse_button.x, event->mouse_button.y };
+    } else if(event->type == MGL_EVENT_MOUSE_BUTTON_RELEASED && event->mouse_button.button == MGL_BUTTON_LEFT) {
+        self->moving_scrollbar = false;
+    }
 
     if(self->child)
         mgui_widget_on_event(self->child, window, event);
 }
 
-/* TODO: Check if visible in scissor */
+static void mgui_scrollview_handle_scrollbar_move(mgui_scrollview *self, mgl_window *window, double scrollbar_height_ratio) {
+    if(mgl_window_is_mouse_button_pressed(window, MGL_BUTTON_LEFT) && self->moving_scrollbar) {
+        mgl_vec2f mouse_move_diff = (mgl_vec2f){
+            window->cursor_position.x - self->scrollbar_move_prev_pos.x,
+            window->cursor_position.y - self->scrollbar_move_prev_pos.y
+        };
+        self->scrollbar_move_prev_pos.x = window->cursor_position.x;
+        self->scrollbar_move_prev_pos.y = window->cursor_position.y;
 
-void mgui_scrollview_draw(mgui_scrollview *self, mgl_window *window) {
-    const double frame_time = mgui_get_frame_time_seconds();
-    self->mouse_scroll.x *= max_float(0.0f, (1.0f - frame_time * SCROLL_DEACCEL));
-    self->mouse_scroll.y *= max_float(0.0f, (1.0f - frame_time * SCROLL_DEACCEL));
+        /* TODO: Handle vertical scrollbar once its added */
+        /* TODO: Not perfect, improve */
+        if(scrollbar_height_ratio != 0.0)
+            self->scroll.y -= (mouse_move_diff.y * (1.0/scrollbar_height_ratio));
+    }
+}
 
-    if(abs_float(self->mouse_scroll.x) < 0.0001f)
-        self->mouse_scroll.x = 0.0f;
+static void mgui_scrollview_draw_child(mgui_scrollview *self, mgl_window *window, double margin_width, double margin_height, double height, double scrollbar_height, mgl_vec2i child_size) {
+    if(!self->child)
+        return;
 
-    if(abs_float(self->mouse_scroll.y) < 0.0001f)
-        self->mouse_scroll.y = 0.0f;
+    mgl_scissor prev_scissor;
+    mgl_window_get_scissor(window, &prev_scissor);
 
-    self->scroll.x += (int)self->mouse_scroll.x;
-    self->scroll.y += (int)self->mouse_scroll.y;
+    mgl_scissor new_scissor = {
+        .position = self->position,
+        .size = (mgl_vec2i){ self->widget.size.x - margin_width, self->widget.size.y - margin_height }
+    };
+    mgl_window_set_scissor(window, &new_scissor);
 
-    mgl_vec2i child_size;
-    if(self->child)
-        child_size = self->child->size;
-    else
-        child_size = (mgl_vec2i){ 0, 0 };
+    mgui_widget_set_position(self->child,
+        (mgl_vec2i){ self->position.x + self->scroll.x + self->child->margin.left, self->position.y + self->scroll.y + self->child->margin.top });
+    mgui_widget_draw(self->child, window);
+
+    mgl_window_set_scissor(window, &prev_scissor);
+
+    {
+        const double scroll_ratio = child_size.y == 0 ? 0.0 : (double)-self->scroll.y / (double)child_size.y;
+        const int scrollbar_offset_y = height * scroll_ratio;
+
+        const int scrollbar_width = 10;
+        const int right = self->widget.size.x - self->widget.margin.left - self->widget.margin.right;
+
+        self->scrollbar_pos = (mgl_vec2f){ self->position.x + right - scrollbar_width, self->position.y + scrollbar_offset_y };
+        self->scrollbar_size = (mgl_vec2f){ scrollbar_width, scrollbar_height };
+
+        mgl_rectangle rect = {
+            .position = self->scrollbar_pos,
+            .size = self->scrollbar_size,
+            .color = { 55, 60, 68, 255 }
+        };
+
+        mgl_rectangle_draw(mgl_get_context(), &rect);
+    }
+}
 
+static void mgui_scrollview_limit_scroll_to_child_size(mgui_scrollview *self, mgl_vec2i child_size) {
     if(child_size.x > self->widget.size.x) {
         self->scroll.x = min_int(self->scroll.x, 0);
         self->scroll.x = max_int(self->scroll.x, -child_size.x + self->widget.size.x);
@@ -124,46 +174,43 @@ void mgui_scrollview_draw(mgui_scrollview *self, mgl_window *window) {
     } else {
         self->scroll.y = 0;
     }
+}
 
-    if(self->child) {
-        mgl_scissor prev_scissor;
-        mgl_window_get_scissor(window, &prev_scissor);
+static void mgui_scrollview_update_mouse_scroll(mgui_scrollview *self, double frame_time) {
+    self->mouse_scroll.x *= max_float(0.0f, (1.0f - frame_time * SCROLL_DEACCEL));
+    self->mouse_scroll.y *= max_float(0.0f, (1.0f - frame_time * SCROLL_DEACCEL));
+
+    if(abs_float(self->mouse_scroll.x) < 0.0001f)
+        self->mouse_scroll.x = 0.0f;
 
-        /* TODO: Fix all this margin crap, it should be invisible */
-        const int margin_width = self->widget.margin.top + self->widget.margin.bottom;
-        const int margin_height = self->widget.margin.top + self->widget.margin.bottom;
+    if(abs_float(self->mouse_scroll.y) < 0.0001f)
+        self->mouse_scroll.y = 0.0f;
 
-        mgl_scissor new_scissor = {
-            .position = self->position,
-            .size = (mgl_vec2i){ self->widget.size.x - margin_width, self->widget.size.y - margin_height }
-        };
-        mgl_window_set_scissor(window, &new_scissor);
-
-        mgui_widget_set_position(self->child,
-            (mgl_vec2i){ self->position.x + self->scroll.x + self->child->margin.left, self->position.y + self->scroll.y + self->child->margin.top });
-        mgui_widget_draw(self->child, window);
-
-        mgl_window_set_scissor(window, &prev_scissor);
-
-        {
-            /* TODO: Fix all this margin crap, it should be invisible */
-            const int margin_height = self->widget.margin.top + self->widget.margin.bottom;
-            const int height = self->widget.size.y - margin_height;
-            const double scrollbar_height_ratio = child_size.y == 0 ? 0.0 : (double)height / (double)child_size.y;
-            const int scrollbar_height = scrollbar_height_ratio * height;
-
-            const double scroll_ratio = child_size.y == 0 ? 0.0 : (double)-self->scroll.y / (double)child_size.y;
-            const int scrollbar_offset_y = height * scroll_ratio;
-
-            const int scrollbar_width = 5;
-            const int right = self->widget.size.x - self->widget.margin.left - self->widget.margin.right;
-            mgl_rectangle rect = {
-                .position = { self->position.x + right - scrollbar_width, self->position.y + scrollbar_offset_y },
-                .size = { scrollbar_width, scrollbar_height },
-                .color = { 55, 60, 68, 255 }
-            };
-
-            mgl_rectangle_draw(mgl_get_context(), &rect);
-        }
-    }
+    self->scroll.x += (int)self->mouse_scroll.x;
+    self->scroll.y += (int)self->mouse_scroll.y;
+}
+
+/* TODO: Check if visible in scissor */
+void mgui_scrollview_draw(mgui_scrollview *self, mgl_window *window) {
+    const double frame_time = mgui_get_frame_time_seconds();
+    mgui_scrollview_update_mouse_scroll(self, frame_time);
+
+    mgl_vec2i child_size;
+    if(self->child)
+        child_size = self->child->size;
+    else
+        child_size = (mgl_vec2i){ 0, 0 };
+
+    /* TODO: Fix all this margin crap, it should be invisible */
+    const int margin_width = self->widget.margin.top + self->widget.margin.bottom;
+    const int margin_height = self->widget.margin.top + self->widget.margin.bottom;
+
+    /* TODO: Fix all this margin crap, it should be invisible */
+    const int height = self->widget.size.y - margin_height;
+    const double scrollbar_height_ratio = child_size.y == 0 ? 0.0 : (double)height / (double)child_size.y;
+    const int scrollbar_height = scrollbar_height_ratio * height;
+
+    mgui_scrollview_handle_scrollbar_move(self, window, scrollbar_height_ratio);
+    mgui_scrollview_limit_scroll_to_child_size(self, child_size);
+    mgui_scrollview_draw_child(self, window, margin_width, margin_height, height, scrollbar_height, child_size);
 }