== Simple Title Cards for Sequencer ==

This commit adds an experimental effect strip to the sequencer: "Title
Card".

This is useful for adding simple one-line text section headers or
"title cards" (i.e. title + author/contact details) to video clips,
which is often seen in demo videos accompanying papers and/or
animation tests.

See http://aligorith.blogspot.com/2011/06/gsoc11-simple-title-
cards.html for some more details on usage.

Code notes:
- There are a few things I've done here which will probably need
cleaning up. For instance, the hacks to get threadsafe fonts for
rendering, and also the way I've tried to piggyback the backdrop
drawing on top of the Solid Colour strips (this method was used to
keep changes here minimal, but is quite fragile if things change).

11 files changed, 204 insertions, 4 deletions

diff --git a/source/blender/blenfont/BLF_api.h b/source/blender/blenfont/BLF_api.h
index 57f8c83eda6..fba09ee9826 100644
--- a/source/blender/blenfont/BLF_api.h
+++ b/source/blender/blenfont/BLF_api.h
@@ -215,5 +215,6 @@ void BLF_dir_free(char **dirs, int count);
 // XXX, bad design
 extern int blf_mono_font;
 extern int blf_mono_font_render; // dont mess drawing with render threads.
+extern int blf_default_font_render; // dont mess drawing with render threads.
 
 #endif /* BLF_API_H */
diff --git a/source/blender/blenfont/intern/blf.c b/source/blender/blenfont/intern/blf.c
index c0e62b1c0c7..3bfb7c22082 100644
--- a/source/blender/blenfont/intern/blf.c
+++ b/source/blender/blenfont/intern/blf.c
@@ -74,6 +74,7 @@ static int global_font_dpi= 72;
 // XXX, should these be made into global_font_'s too?
 int blf_mono_font= -1;
 int blf_mono_font_render= -1;
+int blf_default_font_render= -1;
 
 static FontBLF *BLF_get(int fontid)
 {
diff --git a/source/blender/blenkernel/intern/seqeffects.c b/source/blender/blenkernel/intern/seqeffects.c
index fbb5a77fa04..688fdd8ff49 100644
--- a/source/blender/blenkernel/intern/seqeffects.c
+++ b/source/blender/blenkernel/intern/seqeffects.c
@@ -40,8 +40,11 @@
 #include "BLI_dynlib.h"
 
 #include "BLI_math.h" /* windows needs for M_PI */
+#include "BLI_string.h"
 #include "BLI_utildefines.h"
 
+#include "BLF_api.h"
+
 #include "DNA_scene_types.h"
 #include "DNA_sequence_types.h"
 #include "DNA_anim_types.h"
@@ -2805,6 +2808,130 @@ static struct ImBuf * do_solid_color(
 }
 
 /* **********************************************************************
+   TITLE CARD
+   ********************************************************************** */
+
+static void init_title_card(Sequence *seq)
+{
+	TitleCardVars *tv;
+	
+	if(seq->effectdata)MEM_freeN(seq->effectdata);
+	seq->effectdata = MEM_callocN(sizeof(struct TitleCardVars), "titlecard");
+	
+	tv = (TitleCardVars *)seq->effectdata;
+	
+	BLI_strncpy(tv->titlestr, "Title goes here", sizeof(tv->titlestr));
+	tv->fgcol[0] = tv->fgcol[1] = tv->fgcol[2] = 1.0f; /* white */
+}
+
+static int num_inputs_titlecard(void)
+{
+	return 0;
+}
+
+static void free_title_card(Sequence *seq)
+{
+	if(seq->effectdata)MEM_freeN(seq->effectdata);
+	seq->effectdata = NULL;
+}
+
+static void copy_title_card(Sequence *dst, Sequence *src)
+{
+	dst->effectdata = MEM_dupallocN(src->effectdata);
+}
+
+static int early_out_titlecard(struct Sequence *UNUSED(seq),
+			   float UNUSED(facf0), float UNUSED(facf1))
+{
+	return -1;
+}
+
+static struct ImBuf * do_title_card(
+	SeqRenderData context, Sequence *seq, float cfra,
+	float facf0, float facf1, 
+	struct ImBuf *ibuf1, struct ImBuf *ibuf2, 
+	struct ImBuf *ibuf3)
+{	
+	TitleCardVars *tv = (TitleCardVars *)seq->effectdata;
+	
+	SolidColorVars cv = {{0}};
+	struct ImBuf *out;
+	
+	int titleFontId = blf_default_font_render; // XXX: bad design!
+	
+	int width = context.rectx;
+	int height = context.recty;
+	float w, h;
+	int x, y;
+	
+	/* use fake solid-color vars to get backdrop (and an out buffer at the same time) */
+	VECCOPY(cv.col, tv->bgcol);
+	seq->effectdata = &cv;
+	
+	out = do_solid_color(context, seq, cfra,
+			facf0, facf1,
+			ibuf1, ibuf2, ibuf3);
+			
+	seq->effectdata = tv;
+	
+	/* draw text */
+	/* FIXME: imbuf out->rect is unsigned int NOT unsigned char, but without passing this pointer
+	 * this drawing code doesn't work. This cast really masks some potential bugs though...
+	 */
+	BLF_buffer(titleFontId, out->rect_float, (unsigned char *)out->rect, width, height, 4);
+	
+	if (tv->titlestr[0]) {
+		/* automatic scale - these formulae have been derived experimentally:
+		 *	- base size is based on 40pt at 960 width
+		 *	- each 26 characters, size jumps down one step, 
+		 *	  but this decrease needs to be exponential to fit everything
+		 */
+		float lfac = strlen(tv->titlestr) / 26.0f;
+		float size = (width * 0.06f) * (1.0f - 0.1f*lfac*lfac);
+		
+		BLF_size(titleFontId, size, 72);
+		BLF_buffer_col(titleFontId, tv->fgcol[0], tv->fgcol[1], tv->fgcol[2], 1.0);
+		
+		BLF_width_and_height(titleFontId, tv->titlestr, &w, &h);
+		x = width/2.0f - w/2.0f;
+		if (tv->subtitle[0])
+			y = height/2.0f + h;
+		else
+			y = height/2.0f;
+		
+		BLF_position(titleFontId, x, y, 0.0);
+		BLF_draw_buffer(titleFontId, tv->titlestr);
+	}
+	
+	if (tv->subtitle[0]) {
+		/* automatic scale - these formulae have been derived experimentally (as above):
+		 *	- base size is based on 20pt at 960 width
+		 *	- size steps aren't quite as refined here. Need a slower-growing curve!
+		 */
+		float lfac = strlen(tv->subtitle) / 36.0f;
+		float size = (width * 0.03f) * (1.0f - 0.1f*lfac*lfac*log(lfac));
+		
+		BLF_size(titleFontId, size, 72);
+		BLF_buffer_col(titleFontId, tv->fgcol[0], tv->fgcol[1], tv->fgcol[2], 1.0);
+		
+		BLF_width_and_height(titleFontId, tv->subtitle, &w, &h);
+		x = width/2.0f - w/2.0f;
+		if (tv->titlestr[0])
+			y = height/2.0f - h;
+		else
+			y = height/2.0f;
+		
+		BLF_position(titleFontId, x, y, 0.0);
+		BLF_draw_buffer(titleFontId, tv->subtitle);
+	}
+	
+	/* cleanup the buffer. */
+	BLF_buffer(UIFONT_DEFAULT, NULL, NULL, 0, 0, 0);
+	
+	return out;
+}
+
+/* **********************************************************************
    MULTICAM
    ********************************************************************** */
 
@@ -3343,6 +3470,14 @@ static struct SeqEffectHandle get_sequence_effect_impl(int seq_type)
 		rval.early_out = early_out_adjustment;
 		rval.execute = do_adjustment;
 		break;
+	case SEQ_TITLECARD:
+		rval.init = init_title_card;
+		rval.num_inputs = num_inputs_titlecard;
+		rval.early_out = early_out_titlecard;
+		rval.free = free_title_card;
+		rval.copy = copy_title_card;
+		rval.execute = do_title_card;
+		break;
 	}
 
 	return rval;
diff --git a/source/blender/blenkernel/intern/sequencer.c b/source/blender/blenkernel/intern/sequencer.c
index b82ac69fc9e..550b81e8a0f 100644
--- a/source/blender/blenkernel/intern/sequencer.c
+++ b/source/blender/blenkernel/intern/sequencer.c
@@ -895,6 +895,7 @@ static const char *give_seqname_by_type(int type)
 	case SEQ_MULTICAM:   return "Multicam";
 	case SEQ_ADJUSTMENT: return "Adjustment";
 	case SEQ_SPEED:      return "Speed";
+	case SEQ_TITLECARD:  return "Title Card";
 	default:
 		return NULL;
 	}
@@ -3020,7 +3021,7 @@ Sequence *seq_foreground_frame_get(Scene *scene, int frame)
 		if(seq->flag & SEQ_MUTE || seq->startdisp > frame || seq->enddisp <= frame)
 			continue;
 		/* only use elements you can see - not */
-		if (ELEM5(seq->type, SEQ_IMAGE, SEQ_META, SEQ_SCENE, SEQ_MOVIE, SEQ_COLOR)) {
+		if (ELEM6(seq->type, SEQ_IMAGE, SEQ_META, SEQ_SCENE, SEQ_MOVIE, SEQ_COLOR, SEQ_TITLECARD)) {
 			if (seq->machine > best_machine) {
 				best_seq = seq;
 				best_machine = seq->machine;
diff --git a/source/blender/blenloader/intern/writefile.c b/source/blender/blenloader/intern/writefile.c
index 240e8d00ab8..fb5c96cd854 100644
--- a/source/blender/blenloader/intern/writefile.c
+++ b/source/blender/blenloader/intern/writefile.c
@@ -1892,6 +1892,9 @@ static void write_scenes(WriteData *wd, ListBase *scebase)
 						case SEQ_TRANSFORM:
 							writestruct(wd, DATA, "TransformVars", 1, seq->effectdata);
 							break;
+						case SEQ_TITLECARD:
+							writestruct(wd, DATA, "TitleCardVars", 1, seq->effectdata);
+							break;
 						}
 					}
 					
diff --git a/source/blender/editors/interface/interface_style.c b/source/blender/editors/interface/interface_style.c
index 2e4106b3c04..1352648b271 100644
--- a/source/blender/editors/interface/interface_style.c
+++ b/source/blender/editors/interface/interface_style.c
@@ -295,6 +295,7 @@ void uiStyleInit(void)
 {
 	uiFont *font= U.uifonts.first;
 	uiStyle *style= U.uistyles.first;
+	int defaultFontId = -1;
 	
 	/* recover from uninitialized dpi */
 	if(U.dpi == 0)
@@ -314,6 +315,7 @@ void uiStyleInit(void)
 		
 		if(font->uifont_id==UIFONT_DEFAULT) {
 			font->blf_id= BLF_load_mem("default", (unsigned char*)datatoc_bfont_ttf, datatoc_bfont_ttf_size);
+			defaultFontId = font->blf_id;
 		}		
 		else {
 			font->blf_id= BLF_load(font->filename);
@@ -351,6 +353,14 @@ void uiStyleInit(void)
 		blf_mono_font_render= BLF_load_mem_unique("monospace", (unsigned char *)datatoc_bmonofont_ttf, datatoc_bmonofont_ttf_size);
 
 	BLF_size(blf_mono_font_render, 12, 72);
+	
+	/* also another copy of default for rendering else we get threading problems */
+	if (defaultFontId != -1) {
+		if (blf_default_font_render == -1)
+			blf_default_font_render= BLF_load_mem_unique("default", (unsigned char*)datatoc_bfont_ttf, datatoc_bfont_ttf_size);
+			
+		BLF_size(blf_default_font_render, 12, 72);
+	}
 }
 
 void uiStyleFontSet(uiFontStyle *fs)
diff --git a/source/blender/editors/space_sequencer/sequencer_draw.c b/source/blender/editors/space_sequencer/sequencer_draw.c
index 119c5da309e..e1efd5b4622 100644
--- a/source/blender/editors/space_sequencer/sequencer_draw.c
+++ b/source/blender/editors/space_sequencer/sequencer_draw.c
@@ -127,6 +127,7 @@ static void get_seq_color3ubv(Scene *curscene, Sequence *seq, unsigned char col[
 	case SEQ_GLOW:
 	case SEQ_MULTICAM:
 	case SEQ_ADJUSTMENT:
+	case SEQ_TITLECARD:
 		UI_GetThemeColor3ubv(TH_SEQ_EFFECT, col);
 		
 		/* slightly offset hue to distinguish different effects */
diff --git a/source/blender/editors/space_sequencer/sequencer_edit.c b/source/blender/editors/space_sequencer/sequencer_edit.c
index c8965c4d3db..46638007fb1 100644
--- a/source/blender/editors/space_sequencer/sequencer_edit.c
+++ b/source/blender/editors/space_sequencer/sequencer_edit.c
@@ -98,9 +98,10 @@ EnumPropertyItem sequencer_prop_effect_types[] = {
 	{SEQ_GLOW, "GLOW", 0, "Glow", "Glow effect strip type"},
 	{SEQ_TRANSFORM, "TRANSFORM", 0, "Transform", "Transform effect strip type"},
 	{SEQ_COLOR, "COLOR", 0, "Color", "Color effect strip type"},
-	{SEQ_SPEED, "SPEED", 0, "Speed", "Color effect strip type"},
+	{SEQ_SPEED, "SPEED", 0, "Speed", ""},
 	{SEQ_MULTICAM, "MULTICAM", 0, "Multicam Selector", ""},
 	{SEQ_ADJUSTMENT, "ADJUSTMENT", 0, "Adjustment Layer", ""},
+	{SEQ_TITLECARD, "TITLE_CARD", 0, "Title Card", ""},
 	{0, NULL, 0, NULL, NULL}
 };
 
@@ -408,6 +409,7 @@ int event_to_efftype(int event)
 	if(event==16) return SEQ_COLOR;
 	if(event==17) return SEQ_SPEED;
 	if(event==18) return SEQ_ADJUSTMENT;
+	if(event==19) return SEQ_TITLECARD;
 	return 0;
 }
 
@@ -520,7 +522,8 @@ static void change_sequence(Scene *scene)
 				"|Transform%x15"
 				"|Color Generator%x16"
 				"|Speed Control%x17"
-				"|Adjustment Layer%x18");
+				"|Adjustment Layer%x18"
+				"|Title Card%x19");
 		if(event > 0) {
 			if(event==1) {
 				SWAP(Sequence *,last_seq->seq1,last_seq->seq2);
diff --git a/source/blender/makesdna/DNA_sequence_types.h b/source/blender/makesdna/DNA_sequence_types.h
index 3e7654bcf47..b9bea7a89b0 100644
--- a/source/blender/makesdna/DNA_sequence_types.h
+++ b/source/blender/makesdna/DNA_sequence_types.h
@@ -227,6 +227,14 @@ typedef struct SolidColorVars {
 	float pad;
 } SolidColorVars;
 
+typedef struct TitleCardVars {
+	char titlestr[64];
+	char subtitle[128];
+	
+	float fgcol[3];
+	float bgcol[3];
+} TitleCardVars;
+
 typedef struct SpeedControlVars {
 	float * frameMap;
 	float globalSpeed;
@@ -314,7 +322,8 @@ typedef struct SpeedControlVars {
 #define SEQ_SPEED               29
 #define SEQ_MULTICAM            30
 #define SEQ_ADJUSTMENT          31
-#define SEQ_EFFECT_MAX          31
+#define SEQ_TITLECARD			40
+#define SEQ_EFFECT_MAX          40
 
 #define STRIPELEM_FAILED       0
 #define STRIPELEM_OK           1
diff --git a/source/blender/makesrna/RNA_access.h b/source/blender/makesrna/RNA_access.h
index ca19a86e42c..d1883b77697 100644
--- a/source/blender/makesrna/RNA_access.h
+++ b/source/blender/makesrna/RNA_access.h
@@ -534,6 +534,7 @@ extern StructRNA RNA_ThemeWidgetColors;
 extern StructRNA RNA_ThemeWidgetStateColors;
 extern StructRNA RNA_TimelineMarker;
 extern StructRNA RNA_Timer;
+extern StructRNA RNA_TitleCardSequence;
 extern StructRNA RNA_ToolSettings;
 extern StructRNA RNA_TouchSensor;
 extern StructRNA RNA_TrackToConstraint;
diff --git a/source/blender/makesrna/intern/rna_sequencer.c b/source/blender/makesrna/intern/rna_sequencer.c
index 8c4e4d9e736..eb2d38e9778 100644
--- a/source/blender/makesrna/intern/rna_sequencer.c
+++ b/source/blender/makesrna/intern/rna_sequencer.c
@@ -418,6 +418,8 @@ static StructRNA* rna_Sequence_refine(struct PointerRNA *ptr)
 			return &RNA_ColorSequence;
 		case SEQ_SPEED:
 			return &RNA_SpeedControlSequence;
+		case SEQ_TITLECARD:
+			return &RNA_TitleCardSequence;
 		default:
 			return &RNA_Sequence;
 	}
@@ -886,6 +888,7 @@ static void rna_def_sequence(BlenderRNA *brna)
 		{SEQ_SPEED, "SPEED", 0, "Speed", ""}, 
 		{SEQ_MULTICAM, "MULTICAM", 0, "Multicam Selector", ""},
 		{SEQ_ADJUSTMENT, "ADJUSTMENT", 0, "Adjustment Layer", ""},
+		{SEQ_TITLECARD, "TITLE_CARD", 0, "Title Card", ""},
 		{0, NULL, 0, NULL, NULL}};
 
 	static const EnumPropertyItem blend_mode_items[]= {
@@ -1666,6 +1669,37 @@ static void rna_def_speed_control(BlenderRNA *brna)
 	RNA_def_property_update(prop, NC_SCENE|ND_SEQUENCER, "rna_Sequence_update");
 }
 
+static void rna_def_title_card(BlenderRNA *brna)
+{
+	StructRNA *srna;
+	PropertyRNA *prop;
+
+	srna = RNA_def_struct(brna, "TitleCardSequence", "EffectSequence");
+	RNA_def_struct_ui_text(srna, "Title Card Sequence", "Sequence strip creating an image displaying some text on a plain color background");
+	RNA_def_struct_sdna_from(srna, "TitleCardVars", "effectdata");
+	
+	/* texts */
+	prop= RNA_def_property(srna, "title", PROP_STRING, PROP_NONE);
+	RNA_def_property_string_sdna(prop, NULL, "titlestr");
+	RNA_def_property_ui_text(prop, "Title", "Text for main heading");
+	RNA_def_property_update(prop, NC_SCENE|ND_SEQUENCER, "rna_Sequence_update");
+	
+	prop= RNA_def_property(srna, "subtitle", PROP_STRING, PROP_NONE);
+	RNA_def_property_ui_text(prop, "Subtitle", "Additional text to be shown under the main heading");
+	RNA_def_property_update(prop, NC_SCENE|ND_SEQUENCER, "rna_Sequence_update");
+	
+	/* colors */
+	prop= RNA_def_property(srna, "color_background", PROP_FLOAT, PROP_COLOR);
+	RNA_def_property_float_sdna(prop, NULL, "bgcol");
+	RNA_def_property_ui_text(prop, "Background Color", "");
+	RNA_def_property_update(prop, NC_SCENE|ND_SEQUENCER, "rna_Sequence_update");
+	
+	prop= RNA_def_property(srna, "color_foreground", PROP_FLOAT, PROP_COLOR);
+	RNA_def_property_float_sdna(prop, NULL, "fgcol");
+	RNA_def_property_ui_text(prop, "Text Color", "");
+	RNA_def_property_update(prop, NC_SCENE|ND_SEQUENCER, "rna_Sequence_update");
+}
+
 void RNA_def_sequencer(BlenderRNA *brna)
 {
 	rna_def_strip_element(brna);
@@ -1691,6 +1725,7 @@ void RNA_def_sequencer(BlenderRNA *brna)
 	rna_def_transform(brna);
 	rna_def_solid_color(brna);
 	rna_def_speed_control(brna);
+	rna_def_title_card(brna);
 }
 
 #endif