fosphor: Add a color intensity scale on the right side

Signed-off-by: Sylvain Munaut <tnt@246tNt.com>

lib/fosphor/fosphor.c

@@ -186,7 +186,8 @@ fosphor_render_defaults(struct fosphor_render *render)
 		FRO_WATERFALL	|
 		FRO_LABEL_FREQ	|
 		FRO_LABEL_PWR	|
-		FRO_LABEL_TIME;
+		FRO_LABEL_TIME	|
+		FRO_COLOR_SCALE;
 
 	render->histo_wf_ratio = 0.5f;
 	render->freq_n_div     = 10;
@@ -199,7 +200,7 @@ void
 fosphor_render_refresh(struct fosphor_render *render)
 {
 	int disp_spectrum, disp_waterfall;
-	int avail, div, over, rsvd;
+	int avail, div, over, rsvd, rsvd_lr[2];
 	float y_top, y_bot;
 
 	/* Which screen zone ? */
@@ -207,10 +208,16 @@ fosphor_render_refresh(struct fosphor_render *render)
 	disp_waterfall = !!(render->options & FRO_WATERFALL);
 
 	/* Split the X space */
+	rsvd_lr[0] = 10;
+	rsvd_lr[1] = 10;
+
 	if (render->options & (FRO_LABEL_PWR | FRO_LABEL_TIME))
-		rsvd = 50;
-	else
-		rsvd = 20;
+		rsvd_lr[0] += 30;
+
+	if (render->options & FRO_COLOR_SCALE)
+		rsvd_lr[1] += 10;
+
+	rsvd = rsvd_lr[0] + rsvd_lr[1];
 
 	render->freq_n_div = ((int)(render->width - rsvd) / 80) & ~1;
 	if (render->freq_n_div > 10)
@@ -223,7 +230,7 @@ fosphor_render_refresh(struct fosphor_render *render)
 	over  = avail - (render->freq_n_div * div);
 
 	render->_x_div = (float)div;
-	render->_x[0] = render->pos_x + (float)(rsvd - 10) + (float)(over / 2);
+	render->_x[0] = render->pos_x + (float)(rsvd_lr[0]) + (float)(over / 2);
 	render->_x[1] = render->_x[0] + (render->freq_n_div * render->_x_div) + 1.0f;
 	render->_x_label = render->_x[0] - 5.0f;
 

lib/fosphor/fosphor.h

@@ -69,6 +69,7 @@ struct fosphor_channel
 #define FRO_LABEL_PWR	(1<<5)	/*!< \brief Display power labels */
 #define FRO_LABEL_TIME	(1<<6)	/*!< \brief Display time labels */
 #define FRO_CHANNELS	(1<<7)	/*!< \brief Display channels */
+#define FRO_COLOR_SCALE	(1<<8)	/*!< \brief Display intensity color scale */
 
 /*! \brief fosphor render options */
 struct fosphor_render

lib/fosphor/gl.c

@@ -429,6 +429,10 @@ fosphor_gl_draw(struct fosphor *self, struct fosphor_render *render)
 		glEnd();
 
 		fosphor_gl_cmap_disable();
+
+		if (render->options & FRO_COLOR_SCALE)
+			fosphor_gl_cmap_draw_scale(gl->cmap_waterfall,
+						   x[1]+2.0f, x[1]+10.0f, y[0], y[1]);
 	}
 
 	/* Draw histogram */
@@ -458,6 +462,10 @@ fosphor_gl_draw(struct fosphor *self, struct fosphor_render *render)
 		glEnd();
 
 		fosphor_gl_cmap_disable();
+
+		if (render->options & FRO_COLOR_SCALE)
+			fosphor_gl_cmap_draw_scale(gl->cmap_waterfall,
+						   x[1]+2.0f, x[1]+10.0f, y[0], y[1]);
 	}
 	else if (render->options & (FRO_LIVE | FRO_MAX_HOLD))
 	{

lib/fosphor/gl_cmap.c

@@ -272,6 +272,29 @@ fosphor_gl_cmap_disable(void)
 	glUseProgram(0);
 }
 
+void
+fosphor_gl_cmap_draw_scale(GLuint cmap_id,
+                           float x0, float x1, float y0, float y1)
+{
+	/* Enable texture-1D */
+	glActiveTexture(GL_TEXTURE0);
+	glBindTexture(GL_TEXTURE_1D, cmap_id);
+	glEnable(GL_TEXTURE_1D);
+
+	glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
+
+	/* Draw QUAD */
+	glBegin( GL_QUADS );
+	glTexCoord1f(0.0f); glVertex2f(x0, y0);
+	glTexCoord1f(0.0f); glVertex2f(x1, y0);
+	glTexCoord1f(1.0f); glVertex2f(x1, y1);
+	glTexCoord1f(1.0f); glVertex2f(x0, y1);
+	glEnd();
+
+	/* Disable texturing */
+	glDisable(GL_TEXTURE_1D);
+}
+
 
 int
 fosphor_gl_cmap_generate(GLuint *cmap_id, gl_cmap_gen_func_t gfn, int N)

lib/fosphor/gl_cmap.h

@@ -53,6 +53,9 @@ void fosphor_gl_cmap_enable(struct fosphor_gl_cmap_ctx *cmap_ctx,
                             enum fosphor_gl_cmap_mode mode);
 void fosphor_gl_cmap_disable(void);
 
+void fosphor_gl_cmap_draw_scale(GLuint cmap_id,
+                                float x0, float x1, float y0, float y1);
+
 typedef void (*gl_cmap_gen_func_t)(uint32_t *rgba, int N);
 int fosphor_gl_cmap_generate(GLuint *cmap_id, gl_cmap_gen_func_t gfn, int N);
 

lib/fosphor/main.c

@@ -204,6 +204,7 @@ _update_fosphor(void)
 
 		g_as->render_main.width  = a;
 		g_as->render_main.height = g_as->h;
+		g_as->render_main.options &= ~FRO_COLOR_SCALE;
 
 		g_as->render_zoom.pos_x  = a - 10;
 		g_as->render_zoom.width  = g_as->w - a + 10;
@@ -213,6 +214,7 @@ _update_fosphor(void)
 	{
 		g_as->render_main.width  = g_as->w;
 		g_as->render_main.height = g_as->h;
+		g_as->render_main.options |= FRO_COLOR_SCALE;
 	}
 
 	g_as->render_main.histo_wf_ratio = g_as->ratio;