graphics!

1 files changed, 253 insertions, 0 deletions

diff --git a/src/kernel/window.c b/src/kernel/window.c
new file mode 100644
index 0000000..28798d1
--- /dev/null
+++ b/src/kernel/window.c
@@ -0,0 +1,253 @@
+#include "paging.h"
+#include "window.h"
+#include "drive.h"
+#include "task.h"
+#include "util.h"
+#include "pmap.h"
+#include "log.h"
+
+#define MAX_WINDOWS 64
+#define ACTION_BUFFER_PAGES 1
+#define AB_END(buf) (buf + (ACTION_BUFFER_PAGES * 4096) / sizeof(struct window_action))
+
+#define BACKGROUND(x, y) ((x / 16 + y / 16) % 2 ? 0x14 : 0x07)
+
+static struct window {
+  const volatile void *pixel_buffer_pma;
+  uint16_t width;
+  uint16_t height;
+
+  uint16_t xpos;
+  uint16_t ypos;
+
+  struct window_action *action_buffer;
+  struct window_action *next_action_read;
+  struct window_action *next_action_write;
+
+  struct window *above;
+  struct window *below;
+
+  struct task_state *from_task;
+} windows[MAX_WINDOWS];
+
+static struct window *bottom_window = 0;
+static struct window *top_window = 0;
+
+static inline void set_pix(uint16_t x, uint16_t y, uint8_t value) {
+  if ((x < 320) && (y < 200))
+    *(uint8_t *)(0xa0000 + y * 320 + x) = value;
+}
+
+static void paint_and_above(const struct window *w) {
+  switch_to_kernel_cr3();
+  for (const struct window *i = w; i; i = i->above)
+    for (uint16_t y = 0; y < i->height; ++y)
+      for (uint16_t x = 0; x < i->width; ++x) {
+        const uint8_t pixel = ((uint8_t *)i->pixel_buffer_pma)[y * i->width + x];
+        if (pixel)
+          set_pix(x + i->xpos, y + i->ypos, pixel);
+      }
+  switch_to_task_cr3();
+}
+
+void paint_bg() {
+  for (uint16_t y = 0; y < 200; ++y)
+    for (uint16_t x = 0; x < 320; ++x)
+      set_pix(x, y, BACKGROUND(x, y));
+}
+
+static void paint_all() {
+  paint_bg();
+  paint_and_above(bottom_window);
+}
+
+struct window *new_window(uint16_t width, uint16_t height, const void *pixel_buffer) {
+  if (!pixel_buffer) {
+    logf(LOG_WARN, "Refusing to create window with null pixel buffer for task %s.", active_task->name);
+    return 0;
+  }
+
+  struct window *w;
+  for (uint8_t i = 0; i < MAX_WINDOWS; ++i)
+    if (!windows[i].pixel_buffer_pma) {
+      w = &windows[i];
+      goto got_window;
+    }
+  return 0;
+got_window:
+
+  w->pixel_buffer_pma = vma_to_pma(active_task->page_directory, pixel_buffer);
+  w->width = width;
+  w->height = height;
+
+  struct window_action *const ab = allocate_kernel_pages(ACTION_BUFFER_PAGES);
+  w->action_buffer = ab;
+  w->next_action_read = ab;
+  w->next_action_write = ab;
+
+  if (top_window)
+    top_window->above = w;
+  else
+    bottom_window = w;
+  w->above = 0;
+  w->below = top_window;
+  top_window = w;
+
+  w->from_task = active_task;
+
+  paint_and_above(w);
+  return w;
+}
+
+void del_window(struct window *w) {
+  if (w == top_window)
+    top_window = w->below;
+  if (w == bottom_window)
+    bottom_window = w->above;
+  if (w->below)
+    w->below->above = w->above;
+  if (w->above)
+    w->above->below = w->below;
+
+  free_pages(w->action_buffer, ACTION_BUFFER_PAGES);
+  w->pixel_buffer_pma = 0;
+
+  paint_all();
+}
+
+void resize_window(struct window *w, uint16_t width, uint16_t height) {
+  const bool smaller = (width < w->width) || (height < w->height);
+
+  w->width = width;
+  w->height = height;
+
+  if (smaller)
+    paint_all();
+  else
+    paint_and_above(w);
+}
+
+void reassign_pixel_buffer(struct window *w, const void *pixel_buffer) {
+  w->pixel_buffer_pma = vma_to_pma(active_task->page_directory, pixel_buffer);
+}
+
+void push_window_paint(const struct window *w) {
+  paint_and_above(w);
+}
+
+struct window_action next_window_action(struct window *w) {
+  if (w->next_action_write == w->next_action_read)
+    return (struct window_action){.action_type = NONE};
+  const struct window_action *const action = w->next_action_read;
+  if (++(w->next_action_read) >= AB_END(w->action_buffer))
+    w->next_action_read = w->action_buffer;
+  return *action;
+}
+
+static void send_action(struct window *w, struct window_action packet) {
+  struct window_action *next_next = w->next_action_write + 1;
+  if (next_next >= AB_END(w->action_buffer))
+    next_next = w->action_buffer;
+  if (next_next != w->next_action_read) {
+    *(w->next_action_write) = packet;
+    w->next_action_write = next_next;
+    unwait(w->from_task, (struct wait){.mode = WINDOW_ACTION});
+  }
+}
+
+enum wm_action {
+  WM_SHUFFLE_UP,
+  WM_SHUFFLE_DOWN,
+  WM_MOVE_LEFT,
+  WM_MOVE_RIGHT,
+  WM_MOVE_UP,
+  WM_MOVE_DOWN,
+
+  N_WM_ACTIONS
+};
+
+static struct key_packet keybinds[] = {
+  {.key_id = KEY_PAGE_DOWN,   .modifiers = WINS},
+  {.key_id = KEY_PAGE_UP,     .modifiers = WINS},
+  {.key_id = KEY_LEFT_ARROW,  .modifiers = WINS},
+  {.key_id = KEY_RIGHT_ARROW, .modifiers = WINS},
+  {.key_id = KEY_UP_ARROW,    .modifiers = WINS},
+  {.key_id = KEY_DOWN_ARROW,  .modifiers = WINS}
+};
+
+static inline bool fuzzy_key_match(struct key_packet t, struct key_packet a) {
+  if (t.key_id != a.key_id)
+    return false;
+
+  if (((t.modifiers & SHIFTS) == SHIFTS) && (a.modifiers & SHIFTS))
+    a.modifiers |= SHIFTS;
+  if (((t.modifiers & CTRLS)  == CTRLS)  && (a.modifiers & CTRLS))
+    a.modifiers |= CTRLS;
+  if (((t.modifiers & ALTS)   == ALTS)   && (a.modifiers & ALTS))
+    a.modifiers |= ALTS;
+  if (((t.modifiers & WINS)   == WINS)   && (a.modifiers & WINS))
+    a.modifiers |= WINS;
+
+  return a.modifiers == t.modifiers;
+}
+
+#include "log.h"
+
+void on_action(struct window_action packet) {
+//logf(LOG_INFO, "Window action, top window = 0x%d from %s.", top_window, top_window->from_task->name);
+
+  if (packet.action_type == NOT_READY)
+    return;
+
+  if (top_window) {
+    if (packet.action_type == KEY_DOWN)
+      for (uint8_t i = 0; i < N_WM_ACTIONS; ++i)
+        if (fuzzy_key_match(keybinds[i], packet.as_key)) {
+          switch_to_kernel_cr3();
+          struct window *old_top, *old_bottom;
+          switch (i) {
+          case WM_SHUFFLE_UP:
+            old_top = top_window;
+            old_bottom = bottom_window;
+            top_window = old_top->below;
+            top_window->above = 0;
+            old_top->below = 0;
+            old_top->above = old_bottom;
+            old_bottom->below = old_top;
+            bottom_window = old_top;
+            paint_and_above(bottom_window->above);
+            break;
+          case WM_SHUFFLE_DOWN:
+            old_top = top_window;
+            old_bottom = bottom_window;
+            bottom_window = old_bottom->above;
+            bottom_window->below = 0;
+            old_bottom->above = 0;
+            old_bottom->below = old_top;
+            old_top->above = old_bottom;
+            top_window = old_bottom;
+            paint_and_above(top_window);
+            break;
+          case WM_MOVE_LEFT:
+            --top_window->xpos;
+            paint_all();
+            break;
+          case WM_MOVE_RIGHT:
+            ++top_window->xpos;
+            paint_all();
+            break;
+          case WM_MOVE_UP:
+            --top_window->ypos;
+            paint_all();
+            break;
+          case WM_MOVE_DOWN:
+            ++top_window->ypos;
+            paint_all();
+          }
+          switch_to_task_cr3();
+          return;
+        }
+
+    send_action(top_window, packet);
+  }
+}
\ No newline at end of file