Scale waveforms & show clipping

Scale waveforms in sound strips by volume.
If any drawn line exceeds value 1 or -1 it is drawn by red color so user can see point, where clipping occurs.

Reviewers: brecht

Differential Revision: https://developer.blender.org/D4515

1 files changed, 22 insertions, 8 deletions

diff --git a/source/blender/editors/space_sequencer/sequencer_draw.c b/source/blender/editors/space_sequencer/sequencer_draw.c
index 0f935031ecc..8a64b6f39db 100644
--- a/source/blender/editors/space_sequencer/sequencer_draw.c
+++ b/source/blender/editors/space_sequencer/sequencer_draw.c
@@ -191,7 +191,7 @@ void color3ubv_from_seq(Scene *curscene, Sequence *seq, unsigned char col[3])
 }
 
 static void drawseqwave(View2D *v2d, const bContext *C, SpaceSeq *sseq, Scene *scene, Sequence *seq,
-                        float x1, float y1, float x2, float y2, float stepsize, unsigned int pos)
+                        float x1, float y1, float x2, float y2, float stepsize)
 {
 	/*
 	 * x1 is the starting x value to draw the wave,
@@ -257,10 +257,11 @@ static void drawseqwave(View2D *v2d, const bContext *C, SpaceSeq *sseq, Scene *s
 			return;
 		}
 
-		immUniformColor4f(1.0f, 1.0f, 1.0f, 0.5f);
-
 		GPU_blend(true);
-
+		GPUVertFormat *format = immVertexFormat();
+		uint pos = GPU_vertformat_attr_add(format, "pos", GPU_COMP_F32, 2, GPU_FETCH_FLOAT);
+		uint col = GPU_vertformat_attr_add(format, "color", GPU_COMP_F32, 4, GPU_FETCH_FLOAT);
+		immBindBuiltinProgram(GPU_SHADER_2D_FLAT_COLOR);
 		immBegin(GPU_PRIM_TRI_STRIP, length * 2);
 
 		for (i = 0; i < length; i++) {
@@ -286,12 +287,25 @@ static void drawseqwave(View2D *v2d, const bContext *C, SpaceSeq *sseq, Scene *s
 				value2 = (1.0f - f) * value2 + f * waveform->data[p * 3 + 4];
 			}
 
+			value1 *= seq->volume;
+			value2 *= seq->volume;
+
+			if (value2 > 1 || value1 < -1) {
+				immAttr4f(col, 1.0f, 0.0f, 0.0f, 0.5f);
+
+				CLAMP_MAX(value2, 1.0f);
+				CLAMP_MIN(value1, -1.0f);
+			}
+			else {
+				immAttr4f(col, 1.0f, 1.0f, 1.0f, 0.5f);
+			}
+
 			immVertex2f(pos, x1_offset + i * stepsize, ymid + value1 * yscale);
 			immVertex2f(pos, x1_offset + i * stepsize, ymid + value2 * yscale);
 		}
 
 		immEnd();
-
+		immUnbindProgram();
 		GPU_blend(false);
 	}
 }
@@ -771,15 +785,15 @@ static void draw_seq_strip(
 	x1 = seq->startdisp;
 	x2 = seq->enddisp;
 
+	immUnbindProgram();
+
 	/* draw sound wave */
 	if (seq->type == SEQ_TYPE_SOUND_RAM) {
 		if (!(sseq->flag & SEQ_NO_WAVEFORMS)) {
-			drawseqwave(v2d, C, sseq, scene, seq, x1, y1, x2, y2, BLI_rctf_size_x(&ar->v2d.cur) / ar->winx, pos);
+			drawseqwave(v2d, C, sseq, scene, seq, x1, y1, x2, y2, BLI_rctf_size_x(&ar->v2d.cur) / ar->winx);
 		}
 	}
 
-	immUnbindProgram();
-
 	/* draw lock */
 	if (seq->flag & SEQ_LOCK) {
 		GPU_blend(true);