From e164457c02dc02a191dcc44856e04427f49733d6 Mon Sep 17 00:00:00 2001
From: Themaister <maister@archlinux.us>
Date: Tue, 31 Dec 2013 17:15:28 +0100
Subject: [PATCH] Add support for movable overlay elements.

Very useful for visual feedback of analog controls.
---
 input/overlay.c                    | 46 +++++++++++++++++++++++++++---
 media/overlays/example/example.cfg |  7 ++++-
 retroarch.c                        |  3 +-
 3 files changed, 50 insertions(+), 6 deletions(-)

diff --git a/input/overlay.c b/input/overlay.c
index 52f56aec49..7023e3a523 100644
--- a/input/overlay.c
+++ b/input/overlay.c
@@ -47,6 +47,7 @@ struct overlay_desc
    float range_x, range_y;
    float range_x_mod, range_y_mod;
    float mod_x, mod_y, mod_w, mod_h;
+   float delta_x, delta_y;
 
    enum overlay_type type;
    uint64_t key_mask;
@@ -62,6 +63,7 @@ struct overlay_desc
    float range_mod;
 
    bool updated;
+   bool movable;
 };
 
 struct overlay
@@ -391,6 +393,12 @@ static bool input_overlay_load_desc(input_overlay_t *ol, config_file_t *conf, st
    desc->range_mod = range_mod;
    config_get_float(conf, conf_key, &desc->range_mod);
 
+   snprintf(conf_key, sizeof(conf_key), "overlay%u_desc%u_movable", ol_index, desc_index);
+   desc->movable = false;
+   desc->delta_x = 0.0f;
+   desc->delta_y = 0.0f;
+   config_get_bool(conf, conf_key, &desc->movable);
+
    desc->range_x_mod = desc->range_x;
    desc->range_y_mod = desc->range_y;
 
@@ -762,12 +770,24 @@ void input_overlay_poll(input_overlay_t *ol, input_overlay_state_t *out, int16_t
       }
       else
       {
-         float x_val = (x - desc->x) / desc->range_x_mod / desc->analog_saturate_pct;
-         float y_val = (y - desc->y) / desc->range_y_mod / desc->analog_saturate_pct;
+         float x_dist = x - desc->x;
+         float y_dist = y - desc->y;
+         float x_val = x_dist / desc->range_x_mod;
+         float y_val = y_dist / desc->range_y_mod;
+         float x_val_sat = x_val / desc->analog_saturate_pct;
+         float y_val_sat = y_val / desc->analog_saturate_pct;
 
          unsigned int base = (desc->type == OVERLAY_TYPE_ANALOG_RIGHT) ? 2 : 0;
-         out->analog[base + 0] = clamp(x_val, -1.0f, 1.0f) * 32767.0f;
-         out->analog[base + 1] = clamp(y_val, -1.0f, 1.0f) * 32767.0f;
+         out->analog[base + 0] = clamp(x_val_sat, -1.0f, 1.0f) * 32767.0f;
+         out->analog[base + 1] = clamp(y_val_sat, -1.0f, 1.0f) * 32767.0f;
+      }
+
+      if (desc->movable)
+      {
+         float x_dist = x - desc->x;
+         float y_dist = y - desc->y;
+         desc->delta_x = clamp(x_dist, -desc->range_x, desc->range_x) * ol->active->mod_w;
+         desc->delta_y = clamp(y_dist, -desc->range_y, desc->range_y) * ol->active->mod_h;
       }
    }
 
@@ -777,6 +797,19 @@ void input_overlay_poll(input_overlay_t *ol, input_overlay_state_t *out, int16_t
       memset(out, 0, sizeof(*out));
 }
 
+static void input_overlay_update_desc_geom(input_overlay_t *ol, struct overlay_desc *desc)
+{
+   if (desc->image.image && desc->movable)
+   {
+      ol->iface->vertex_geom(ol->iface_data, desc->image_index,
+            desc->mod_x + desc->delta_x, desc->mod_y + desc->delta_y,
+            desc->mod_w, desc->mod_h);
+
+      desc->delta_x = 0.0f;
+      desc->delta_y = 0.0f;
+   }
+}
+
 void input_overlay_post_poll(input_overlay_t *ol)
 {
    size_t i;
@@ -803,6 +836,7 @@ void input_overlay_post_poll(input_overlay_t *ol)
          desc->range_y_mod = desc->range_y;
       }
 
+      input_overlay_update_desc_geom(ol, desc);
       desc->updated = false;
    }
 }
@@ -819,6 +853,10 @@ void input_overlay_poll_clear(input_overlay_t *ol)
       desc->range_x_mod = desc->range_x;
       desc->range_y_mod = desc->range_y;
       desc->updated = false;
+
+      desc->delta_x = 0.0f;
+      desc->delta_y = 0.0f;
+      input_overlay_update_desc_geom(ol, desc);
    }
 }
 
diff --git a/media/overlays/example/example.cfg b/media/overlays/example/example.cfg
index c9545599b1..ac391321f9 100644
--- a/media/overlays/example/example.cfg
+++ b/media/overlays/example/example.cfg
@@ -8,7 +8,7 @@ overlay0_alpha_mod = 2.0 # If we press a button desc, it will have twice the alp
 overlay0_range_mod = 1.5 # If we press a button desc, the hitbox range will be 1.5x the size until it's released.
 overlay0_normalized = true # Descriptor coordinates use normalized coordinates [0, 1] instead of pixels.
 
-overlay0_descs = 5
+overlay0_descs = 6
 overlay0_desc0_overlay = left.png
 overlay0_desc1_overlay = right.png
 overlay0_desc2_overlay = up.png
@@ -20,3 +20,8 @@ overlay0_desc3 = "down,0.50,0.75,rect,0.125,0.125"
 
 overlay0_desc4 = "nul,0.30,0.90,rect,0.28,0.08" # Paste an arbitrary image. Input associated with this is nul.
 overlay0_desc4_overlay = logo.png
+
+overlay0_desc5 = "analog_left,0.1,0.1,radial,0.10,0.15"
+overlay0_desc5_overlay = analog.png
+overlay0_desc5_range_mod = 2.0
+overlay0_desc5_movable = true
diff --git a/retroarch.c b/retroarch.c
index 186c4e328c..7d0a5c242f 100644
--- a/retroarch.c
+++ b/retroarch.c
@@ -511,8 +511,9 @@ static inline void input_poll_overlay(void)
 
       driver.overlay_state.buttons |= polled_data.buttons;
 
+      // Fingers pressed later take prio and matched up with overlay poll priorities.
       for (j = 0; j < 4; j++)
-         if (!driver.overlay_state.analog[j])
+         if (polled_data.analog[j])
             driver.overlay_state.analog[j] = polled_data.analog[j];
 
       polled = true;