From b7865b732dc41e861496c5bff5d1a1254e927807 Mon Sep 17 00:00:00 2001
From: Drew DeVault <sir@cmpwn.com>
Date: Wed, 4 Jan 2017 03:49:33 -0500
Subject: [PATCH] Add gamma control API

---
 include/wlc/wlc.h              |  6 ++++++
 src/compositor/output.c        | 27 +++++++++++++++++++++++++++
 src/compositor/output.h        |  1 +
 src/platform/backend/backend.h |  2 ++
 src/platform/backend/drm.c     | 16 ++++++++++++++++
 5 files changed, 52 insertions(+)

diff --git a/include/wlc/wlc.h b/include/wlc/wlc.h
index 1d170853..541f305d 100644
--- a/include/wlc/wlc.h
+++ b/include/wlc/wlc.h
@@ -280,6 +280,12 @@ bool wlc_output_get_sleep(wlc_handle output);
 /** Wake up / sleep. */
 void wlc_output_set_sleep(wlc_handle output, bool sleep);
 
+/** Set gamma. R, G, and B are color ramp arrays of size elements. */
+void wlc_output_set_gamma(wlc_handle output, uint16_t size, uint16_t *r, uint16_t *g, uint16_t *b);
+
+/** Get gamma size */
+uint16_t wlc_output_get_gamma_size(wlc_handle output);
+
 /**
  * Get real resolution.
  * Resolution applied by either wlc_output_set_resolution call or initially.
diff --git a/src/compositor/output.c b/src/compositor/output.c
index f64639eb..1ec4b5af 100644
--- a/src/compositor/output.c
+++ b/src/compositor/output.c
@@ -817,6 +817,16 @@ wlc_output_set_sleep_ptr(struct wlc_output *output, bool sleep)
    }
 }
 
+void
+wlc_output_set_gamma_ptr(struct wlc_output *output, uint16_t size, uint16_t *r, uint16_t *g, uint16_t *b)
+{
+   if (!output)
+      return;
+
+   if (output->bsurface.api.set_gamma)
+      output->bsurface.api.set_gamma(&output->bsurface, size, r, g, b);
+}
+
 void
 wlc_output_set_mask_ptr(struct wlc_output *output, uint32_t mask)
 {
@@ -913,6 +923,23 @@ wlc_output_set_sleep(wlc_handle output, bool sleep)
    wlc_output_set_sleep_ptr(convert_from_wlc_handle(output, "output"), sleep);
 }
 
+WLC_API void
+wlc_output_set_gamma(wlc_handle output, uint16_t size, uint16_t *r, uint16_t *g, uint16_t *b)
+{
+   wlc_output_set_gamma_ptr(convert_from_wlc_handle(output, "output"), size, r, g, b);
+}
+
+WLC_API uint16_t
+wlc_output_get_gamma_size(wlc_handle output)
+{
+   struct wlc_output *_output = convert_from_wlc_handle(output, "output");
+
+   if (!_output || _output->bsurface.api.get_gamma_size)
+      return 0;
+
+   return _output->bsurface.api.get_gamma_size(&_output->bsurface);
+}
+
 WLC_API uint32_t
 wlc_output_get_mask(wlc_handle output)
 {
diff --git a/src/compositor/output.h b/src/compositor/output.h
index b26aeae9..d546ffbc 100644
--- a/src/compositor/output.h
+++ b/src/compositor/output.h
@@ -105,6 +105,7 @@ WLC_NONULL bool wlc_output(struct wlc_output *output);
 
 void wlc_output_focus_ptr(struct wlc_output *output);
 void wlc_output_set_sleep_ptr(struct wlc_output *output, bool sleep);
+void wlc_output_set_gamma_ptr(struct wlc_output *output, uint16_t size, uint16_t *r, uint16_t *g, uint16_t *b);
 WLC_NONULLV(2) bool wlc_output_set_resolution_ptr(struct wlc_output *output, const struct wlc_size *resolution, uint32_t scale);
 void wlc_output_set_mask_ptr(struct wlc_output *output, uint32_t mask);
 WLC_NONULLV(2) void wlc_output_get_pixels_ptr(struct wlc_output *output, bool (*pixels)(const struct wlc_size *size, uint8_t *rgba, void *arg), void *arg);
diff --git a/src/platform/backend/backend.h b/src/platform/backend/backend.h
index ec270bb3..6eb8efa3 100644
--- a/src/platform/backend/backend.h
+++ b/src/platform/backend/backend.h
@@ -17,6 +17,8 @@ struct wlc_backend_surface {
       WLC_NONULL void (*terminate)(struct wlc_backend_surface *surface);
       WLC_NONULL void (*sleep)(struct wlc_backend_surface *surface, bool sleep);
       WLC_NONULL bool (*page_flip)(struct wlc_backend_surface *surface);
+      WLC_NONULL void (*set_gamma)(struct wlc_backend_surface *bsurface, uint16_t size, uint16_t *r, uint16_t *g, uint16_t *b);
+      WLC_NONULL uint16_t (*get_gamma_size)(struct wlc_backend_surface *bsurface);
    } api;
 };
 
diff --git a/src/platform/backend/drm.c b/src/platform/backend/drm.c
index 79491022..3e3c420a 100644
--- a/src/platform/backend/drm.c
+++ b/src/platform/backend/drm.c
@@ -190,6 +190,20 @@ surface_sleep(struct wlc_backend_surface *bsurface, bool sleep)
    }
 }
 
+static void
+set_gamma(struct wlc_backend_surface *bsurface, uint16_t size, uint16_t *r, uint16_t *g, uint16_t *b)
+{
+   struct drm_surface *dsurface = bsurface->internal;
+   drmModeCrtcSetGamma(drm.fd, dsurface->crtc->crtc_id, size, r, g, b);
+}
+
+static uint16_t
+get_gamma_size(struct wlc_backend_surface *bsurface)
+{
+   struct drm_surface *dsurface = bsurface->internal;
+   return dsurface->crtc->gamma_size;
+}
+
 static void
 surface_release(struct wlc_backend_surface *bsurface)
 {
@@ -232,6 +246,8 @@ add_output(struct gbm_device *device, struct gbm_surface *surface, struct drm_ou
    bsurface.window = (EGLNativeWindowType)surface;
    bsurface.api.sleep = surface_sleep;
    bsurface.api.page_flip = page_flip;
+   bsurface.api.set_gamma = set_gamma;
+   bsurface.api.get_gamma_size = get_gamma_size;
 
    struct wlc_output_event ev = { .add = { &bsurface, &info->info }, .type = WLC_OUTPUT_EVENT_ADD };
    wl_signal_emit(&wlc_system_signals()->output, &ev);