Basic overlay POC works.

Add support for X11.

Makefile

@@ -13,6 +13,7 @@ OBJ = retroarch.o \
 		rewind.o \
 		gfx/gfx_common.o \
 		input/input_common.o \
+		input/overlay.o \
 		patch.o \
 	   fifo_buffer.o \
 		compat/compat.o \

driver.h

@@ -208,7 +208,7 @@ struct rarch_viewport;
 typedef struct video_overlay_interface
 {
    void (*enable)(void *data, bool state);
-   bool (*load)(void *data, const char *path);
+   bool (*load)(void *data, const uint32_t *image, unsigned width, unsigned height);
    void (*tex_geom)(void *data, float x, float y, float w, float h);
    void (*vertex_geom)(void *data, float x, float y, float w, float h);
 } video_overlay_interface_t;

driver_funcs.h

@@ -42,6 +42,7 @@
 #define video_set_aspect_ratio_func(aspect_idx) driver.video->set_aspect_ratio(driver.video_data, aspect_idx)
 #define video_viewport_info_func(info) driver.video->viewport_info(driver.video_data, info)
 #define video_read_viewport_func(buffer) driver.video->read_viewport(driver.video_data, buffer)
+#define video_overlay_interface_func(iface) driver.video->overlay_interface(driver.video_data, iface)
 #define video_free_func() driver.video->free(driver.video_data)
 #define input_init_func() driver.input->init()
 #define input_poll_func() driver.input->poll(driver.input_data)

gfx/gl.c

@@ -1792,7 +1792,7 @@ static void gl_set_aspect_ratio(void *data, unsigned aspectratio_index)
 }
 #endif
 
-static bool gl_overlay_load(void *data, const char *path)
+static bool gl_overlay_load(void *data, const uint32_t *image, unsigned width, unsigned height)
 {
    gl_t *gl = (gl_t*)data;
 
@@ -1805,19 +1805,11 @@ static bool gl_overlay_load(void *data, const char *path)
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 
-   struct texture_image img = {0};
-   if (!texture_image_load(path, &img))
-   {
-      RARCH_ERR("Failed to load overlay image: %s.\n", path);
-      return false;
-   }
-
-   glPixelStorei(GL_UNPACK_ALIGNMENT, get_alignment(img.width * sizeof(uint32_t)));
+   glPixelStorei(GL_UNPACK_ALIGNMENT, get_alignment(width * sizeof(uint32_t)));
    glTexImage2D(GL_TEXTURE_2D, 0, RARCH_GL_INTERNAL_FORMAT32,
-         img.width, img.height, 0, RARCH_GL_TEXTURE_TYPE32,
-         RARCH_GL_FORMAT32, img.pixels);
+         width, height, 0, RARCH_GL_TEXTURE_TYPE32,
+         RARCH_GL_FORMAT32, image);
 
-   free(img.pixels);
    gl_overlay_tex_geom(gl, 0, 0, 1, 1); // Default. Stretch to whole screen.
    gl_overlay_vertex_geom(gl, 0, 0, 1, 1);
    return true;

input/overlay.c

@@ -0,0 +1,115 @@
+/*  RetroArch - A frontend for libretro.
+ *  Copyright (C) 2010-2012 - Hans-Kristian Arntzen
+ * 
+ *  RetroArch is free software: you can redistribute it and/or modify it under the terms
+ *  of the GNU General Public License as published by the Free Software Found-
+ *  ation, either version 3 of the License, or (at your option) any later version.
+ *
+ *  RetroArch is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+ *  without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
+ *  PURPOSE.  See the GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along with RetroArch.
+ *  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "overlay.h"
+#include "../general.h"
+#include "../driver.h"
+#include "../libretro.h"
+#include "../gfx/image.h"
+
+struct input_overlay
+{
+   void *iface_data;
+   const video_overlay_interface_t *iface;
+};
+
+input_overlay_t *input_overlay_new(const char *overlay)
+{
+   (void)overlay;
+
+   input_overlay_t *ol = (input_overlay_t*)calloc(1, sizeof(*ol));
+   if (!ol)
+      goto error;
+
+   if (!driver.video->overlay_interface)
+   {
+      RARCH_ERR("Overlay interface is not present in video driver.\n");
+      goto error;
+   }
+
+   video_overlay_interface_func(&ol->iface);
+   ol->iface_data = driver.video_data;
+
+   if (!ol->iface)
+      goto error;
+
+   // Test hardcoded.
+   struct texture_image img = {0};
+   if (!texture_image_load("/tmp/test.png", &img))
+   {
+      RARCH_ERR("Failed to load overlay image.\n");
+      goto error;
+   }
+
+   ol->iface->load(ol->iface_data, img.pixels, img.width, img.height);
+   free(img.pixels);
+
+   ol->iface->enable(ol->iface_data, true);
+
+   return ol;
+
+error:
+   input_overlay_free(ol);
+   return NULL;
+}
+
+struct overlay_desc
+{
+   float x;
+   float y;
+   float rad;
+   unsigned key;
+};
+
+// TODO: This will be part of a config of some sort.
+static const struct overlay_desc descs[] = {
+   { 0.25, 0.5, 0.1, RETRO_DEVICE_ID_JOYPAD_LEFT },
+   { 0.75, 0.5, 0.1, RETRO_DEVICE_ID_JOYPAD_RIGHT },
+};
+
+uint64_t input_overlay_poll(input_overlay_t *ol, int16_t norm_x, int16_t norm_y)
+{
+   // norm_x and norm_y is in [-0x7fff, 0x7fff] range, like RETRO_DEVICE_POINTER.
+   float x = (float)(norm_x + 0x7fff) / 0xffff;
+   float y = (float)(norm_y + 0x7fff) / 0xffff;
+
+   uint64_t state = 0;
+   for (unsigned i = 0; i < ARRAY_SIZE(descs); i++)
+   {
+      float sq_dist = (x - descs[i].x) * (x - descs[i].x) + (y - descs[i].y) * (y - descs[i].y);
+      if (sq_dist <= descs[i].rad * descs[i].rad)
+         state |= UINT64_C(1) << descs[i].key;
+   }
+
+   return state;
+}
+
+void input_overlay_next(input_overlay_t *ol)
+{
+   // Dummy
+   (void)ol;
+}
+
+void input_overlay_free(input_overlay_t *ol)
+{
+   if (!ol)
+      return;
+
+   if (ol->iface)
+      ol->iface->enable(ol->iface_data, false);
+
+   free(ol);
+}
+

input/overlay.h

@@ -0,0 +1,39 @@
+/*  RetroArch - A frontend for libretro.
+ *  Copyright (C) 2010-2012 - Hans-Kristian Arntzen
+ * 
+ *  RetroArch is free software: you can redistribute it and/or modify it under the terms
+ *  of the GNU General Public License as published by the Free Software Found-
+ *  ation, either version 3 of the License, or (at your option) any later version.
+ *
+ *  RetroArch is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+ *  without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
+ *  PURPOSE.  See the GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along with RetroArch.
+ *  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef INPUT_OVERLAY_H__
+#define INPUT_OVERLAY_H__
+
+#include "../boolean.h"
+#include <stdint.h>
+
+// Overlay driver acts as a medium between input drivers and video driver.
+// Coordinates are fetched from input driver, and an overlay with pressable actions are
+// displayed on-screen.
+//
+// This interface requires that the video driver has support for the overlay interface.
+typedef struct input_overlay input_overlay_t;
+
+input_overlay_t *input_overlay_new(const char *overlay);
+void input_overlay_free(input_overlay_t *ol);
+
+// norm_x and norm_y are the result of input_translate_coord_viewport().
+// Resulting state is a bitmask of (1 << key_bind_id).
+uint64_t input_overlay_poll(input_overlay_t *ol, int16_t norm_x, int16_t norm_y);
+
+void input_overlay_next(input_overlay_t *ol);
+
+#endif
+

input/x11_input.c

@@ -14,6 +14,7 @@
  */
 
 #include "input_common.h"
+#include "overlay.h"
 
 #include "../driver.h"
 
@@ -30,6 +31,10 @@ typedef struct x11_input
 {
    const rarch_joypad_driver_t *joypad;
 
+   bool ol_defer;
+   input_overlay_t *ol;
+   uint64_t ol_state;
+
    Display *display;
    Window win;
 
@@ -58,6 +63,11 @@ static void *x_input_init(void)
    x11->joypad = input_joypad_init_first();
    input_init_keyboard_lut(rarch_key_map_x11);
 
+   if (driver.video_data) // Video driver isn't initialized yet, init later.
+      x11->ol = input_overlay_new(NULL);
+   else
+      x11->ol_defer = true;
+
    return x11;
 }
 
@@ -87,7 +97,8 @@ static bool x_bind_button_pressed(void *data, int key)
 {
    x11_input_t *x11 = (x11_input_t*)data;
    return x_is_pressed(x11, g_settings.input.binds[0], key) ||
-      input_joypad_pressed(x11->joypad, 0, &g_settings.input.binds[0][key]);
+      input_joypad_pressed(x11->joypad, 0, &g_settings.input.binds[0][key]) ||
+      (x11->ol_state & (UINT64_C(1) << key));
 }
 
 static int16_t x_mouse_state(x11_input_t *x11, unsigned id)
@@ -165,7 +176,8 @@ static int16_t x_input_state(void *data, const struct retro_keybind **binds, uns
    {
       case RETRO_DEVICE_JOYPAD:
          return x_is_pressed(x11, binds[port], id) ||
-            input_joypad_pressed(x11->joypad, port, &binds[port][id]);
+            input_joypad_pressed(x11->joypad, port, &binds[port][id]) ||
+            ((port == 0) && (x11->ol_state & (UINT64_C(1) << id)));
 
       case RETRO_DEVICE_KEYBOARD:
          return x_key_pressed(x11, id);
@@ -194,9 +206,27 @@ static void x_input_free(void *data)
    if (x11->joypad)
       x11->joypad->destroy();
 
+   if (x11->ol)
+      input_overlay_free(x11->ol);
+
    free(data);
 }
 
+static void x_input_poll_overlay(x11_input_t *x11)
+{
+   if (!x11->ol)
+      return;
+
+   if (x11->mouse_l)
+   {
+      int16_t norm_x = 0, norm_y = 0;
+      bool valid = input_translate_coord_viewport(x11->mouse_x, x11->mouse_y, &norm_x, &norm_y);
+      x11->ol_state = valid ? input_overlay_poll(x11->ol, norm_x, norm_y) : 0;
+   }
+   else
+      x11->ol_state = 0;
+}
+
 static void x_input_poll_mouse(x11_input_t *x11)
 {
    Window root_win, child_win;
@@ -218,12 +248,20 @@ static void x_input_poll_mouse(x11_input_t *x11)
    x11->mouse_l = mask & Button1Mask; 
    x11->mouse_m = mask & Button2Mask; 
    x11->mouse_r = mask & Button3Mask; 
+
+   x_input_poll_overlay(x11);
 }
 
 static void x_input_poll(void *data)
 {
    x11_input_t *x11 = (x11_input_t*)data;
 
+   if (x11->ol_defer)
+   {
+      x11->ol = input_overlay_new(NULL);
+      x11->ol_defer = false;
+   }
+
    if (video_focus_func())
       XQueryKeymap(x11->display, x11->state);
    else