basic inline display for a-comp

diff --git a/libs/plugins/a-comp.lv2/a-comp.c b/libs/plugins/a-comp.lv2/a-comp.c
index ccacd8cb40478791249bdcecdbec5b64168adab3..b5f1b5efec5b6eebc9f4dfc762c7d622afb40d3b 100644 (file)
--- a/libs/plugins/a-comp.lv2/a-comp.c
+++ b/libs/plugins/a-comp.lv2/a-comp.c
@@ -14,6 +14,13 @@
 
 #include <math.h>
 #include <stdlib.h>
+#include <string.h>
+#include <stdbool.h>
+
+#ifdef LV2_EXTENDED
+#include <cairo/cairo.h>
+#include "ardour/lv2_extensions.h"
+#endif
 
 #include "lv2/lv2plug.in/ns/lv2core/lv2.h"
 
@@ -57,6 +64,23 @@ typedef struct {
        float old_yl;
        float old_y1;
        float old_yg;
+
+#ifdef LV2_EXTENDED
+       bool                     need_expose;
+       LV2_Inline_Display_Image_Surface surf;
+       cairo_surface_t*         display;
+       LV2_Inline_Display*      queue_draw;
+       uint32_t                 w, h;
+
+       /* ports pointers are only valid during run so we'll
+        * have to cache them for the display, besides
+        * we do want to check for changes
+        */
+       float v_knee;
+       float v_ratio;
+       float v_thresdb;
+       float v_makeup;
+#endif
 } AComp;
 
 static LV2_Handle
@@ -65,10 +89,19 @@ instantiate(const LV2_Descriptor* descriptor,
             const char* bundle_path,
             const LV2_Feature* const* features)
 {
-       AComp* acomp = (AComp*)malloc(sizeof(AComp));
-       acomp->srate = rate;
+       AComp* acomp = (AComp*)calloc(1, sizeof(AComp));
+
+       for (int i=0; features[i]; ++i) {
+#ifdef LV2_EXTENDED
+               if (!strcmp(features[i]->URI, LV2_INLINEDISPLAY__queue_draw)) {
+                       acomp->queue_draw = (LV2_Inline_Display*) features[i]->data;
+               }
+#endif
+       }
 
+       acomp->srate = rate;
        acomp->old_yl=acomp->old_y1=acomp->old_yg=0.f;
+       acomp->need_expose = true;
 
        return (LV2_Handle)acomp;
 }
@@ -176,6 +209,28 @@ run(LV2_Handle instance, uint32_t n_samples)
        float ratio = *(acomp->ratio);
        float thresdb = *(acomp->thresdb);
 
+#ifdef LV2_EXTENDED
+       if (acomp->v_knee != *acomp->knee) {
+               acomp->v_knee = *acomp->knee;
+               acomp->need_expose = true;
+       }
+
+       if (acomp->v_ratio != *acomp->ratio) {
+               acomp->v_ratio = *acomp->ratio;
+               acomp->need_expose = true;
+       }
+
+       if (acomp->v_thresdb != *acomp->thresdb) {
+               acomp->v_thresdb = *acomp->thresdb;
+               acomp->need_expose = true;
+       }
+
+       if (acomp->v_makeup != *acomp->makeup) {
+               acomp->v_makeup = *acomp->makeup;
+               acomp->need_expose = true;
+       }
+#endif
+
        for (i = 0; i < n_samples; i++) {
                in0 = input0[i];
                in1 = input1[i];
@@ -217,6 +272,13 @@ run(LV2_Handle instance, uint32_t n_samples)
                acomp->old_yg = Lyg;
        }
        *(acomp->outlevel) = (max == 0.f) ? -45.f : to_dB(max);
+
+#ifdef LV2_EXTENDED
+       if (acomp->need_expose && acomp->queue_draw) {
+               acomp->need_expose = false;
+               acomp->queue_draw->queue_draw (acomp->queue_draw->handle);
+       }
+#endif
 }
 
 static void
@@ -228,12 +290,102 @@ deactivate(LV2_Handle instance)
 static void
 cleanup(LV2_Handle instance)
 {
+#ifdef LV2_EXTENDED
+       AComp* acomp = (AComp*)instance;
+       if (acomp->display) {
+               cairo_surface_destroy (acomp->display);
+       }
+#endif
+
        free(instance);
 }
 
+
+#ifndef MIN
+#define MIN(A,B) ((A) < (B)) ? (A) : (B)
+#endif
+
+#ifdef LV2_EXTENDED
+static float
+comp_curve (AComp* self, float in) {
+       const float knee = self->v_knee;
+       const float ratio = self->v_ratio;
+       const float makeup = self->v_makeup;
+       const float thresdb = self->v_thresdb;
+
+       const float width = 6.f * knee + 0.01f;
+       float xg, yg;
+
+       yg = 0.f;
+       xg = (in == 0.f) ? -160.f : to_dB (fabs (in));
+
+       if (2.f * (xg - thresdb) < -width) {
+               yg = xg;
+       } else if (2.f * fabs (xg - thresdb) <= width) {
+               yg = xg + (1.f / ratio - 1.f ) * (xg - thresdb + width / 2.f) * (xg - thresdb + width / 2.f) / (2.f * width);
+       } else if (2.f * (xg - thresdb) > width) {
+               yg = thresdb + (xg - thresdb) / ratio;
+       }
+
+       return yg + makeup;
+}
+
+
+static LV2_Inline_Display_Image_Surface *
+render_inline (LV2_Handle instance, uint32_t w, uint32_t max_h)
+{
+       AComp* self = (AComp*)instance;
+       uint32_t h = MIN (ceilf (w * 9.f/16.f), max_h);
+
+       if (!self->display || self->w != w || self->h != h) {
+               if (self->display) cairo_surface_destroy(self->display);
+               self->display = cairo_image_surface_create (CAIRO_FORMAT_ARGB32, w, h);
+               self->w = w;
+               self->h = h;
+       }
+
+       cairo_t* cr = cairo_create (self->display);
+
+       // clear background
+       cairo_rectangle (cr, 0, 0, w, h);
+       cairo_set_source_rgba (cr, .2, .2, .2, 1.0);
+       cairo_fill (cr);
+
+       // TODO draw grid.
+
+       cairo_set_source_rgba (cr, .8, .8, .8, 1.0);
+       cairo_set_line_width(cr, 1.0);
+       cairo_move_to (cr, 0, 0);
+
+       for (uint32_t x = 0; x < w; ++x) {
+               // TODO proper range..
+               float v = x / (float)w;
+               float y_db = comp_curve (self, v);
+               float y = h - h * from_dB (y_db);
+               cairo_line_to (cr, x, y);
+       }
+       cairo_stroke (cr);
+
+
+       // create RGBA surface
+       cairo_destroy (cr);
+       cairo_surface_flush (self->display);
+       self->surf.width = cairo_image_surface_get_width (self->display);
+       self->surf.height = cairo_image_surface_get_height (self->display);
+       self->surf.stride = cairo_image_surface_get_stride (self->display);
+       self->surf.data = cairo_image_surface_get_data  (self->display);
+
+       return &self->surf;
+}
+#endif
+
 static const void*
 extension_data(const char* uri)
 {
+       static const LV2_Inline_Display_Interface display  = { render_inline };
+       if (!strcmp(uri, LV2_INLINEDISPLAY__interface)) {
+               return &display;
+       }
        return NULL;
 }
 

diff --git a/libs/plugins/a-comp.lv2/wscript b/libs/plugins/a-comp.lv2/wscript
index 7feeee73eed9e47d0eb9d86c1f647f61f32ad91e..7b3cbd69ebe87d116ca3593ab2fbbe4b05c384a0 100644 (file)
--- a/libs/plugins/a-comp.lv2/wscript
+++ b/libs/plugins/a-comp.lv2/wscript
@@ -39,8 +39,10 @@ def build(bld):
                   source       = 'a-comp.c',
                   name         = 'a-comp',
                   cflags       = [ '-fPIC' ],
+                  includes     = [ '../../ardour' ],
                   target       = '../../LV2/%s/a-comp' % bundle,
                   install_path = '${LV2DIR}/%s' % bundle,
+                  uselib       = 'CAIRO',
                   use          = 'LV2_1_0_0'
                   )
         obj.env.cshlib_PATTERN = module_pat