obs-filters: Add crop filter

Allows any source to be cropped, though note that this renders to
texture first, so for more optimal results, cropping values should
probably be put in to capture sources that can be cropped as they're
actually rendered by the source.

plugins/obs-filters/CMakeLists.txt

@@ -3,6 +3,7 @@ project(obs-filters)
 set(obs-filters_SOURCES
 	obs-filters.c
 	async-delay-filter.c
+	crop-filter.c
 	mask-filter.c)
 
 add_library(obs-filters MODULE

plugins/obs-filters/crop-filter.c

+#include <obs-module.h>
+#include <graphics/vec2.h>
+
+struct crop_filter_data {
+	obs_source_t                   *context;
+
+	gs_effect_t                    *effect;
+	gs_eparam_t                    *param_mul;
+	gs_eparam_t                    *param_add;
+
+	int                            left;
+	int                            right;
+	int                            top;
+	int                            bottom;
+	uint32_t                       abs_cx;
+	uint32_t                       abs_cy;
+	uint32_t                       width;
+	uint32_t                       height;
+	bool                           absolute;
+};
+
+static const char *crop_filter_get_name(void)
+{
+	return obs_module_text("CropFilter");
+}
+
+static void *crop_filter_create(obs_data_t *settings, obs_source_t *context)
+{
+	struct crop_filter_data *filter = bzalloc(sizeof(*filter));
+	char *effect_path = obs_module_file("crop_filter.effect");
+
+	filter->context = context;
+
+	obs_enter_graphics();
+	filter->effect = gs_effect_create_from_file(effect_path, NULL);
+	obs_leave_graphics();
+
+	bfree(effect_path);
+
+	if (!filter->effect) {
+		bfree(filter);
+		return NULL;
+	}
+
+	filter->param_mul = gs_effect_get_param_by_name(filter->effect,
+			"mul_val");
+	filter->param_add = gs_effect_get_param_by_name(filter->effect,
+			"add_val");
+
+	obs_source_update(context, settings);
+	return filter;
+}
+
+static void crop_filter_destroy(void *data)
+{
+	struct crop_filter_data *filter = data;
+
+	obs_enter_graphics();
+	gs_effect_destroy(filter->effect);
+	obs_leave_graphics();
+
+	bfree(filter);
+}
+
+static void crop_filter_update(void *data, obs_data_t *settings)
+{
+	struct crop_filter_data *filter = data;
+
+	filter->absolute = !obs_data_get_bool(settings, "relative");
+	filter->left = (int)obs_data_get_int(settings, "left");
+	filter->top = (int)obs_data_get_int(settings, "top");
+	filter->right = (int)obs_data_get_int(settings, "right");
+	filter->bottom = (int)obs_data_get_int(settings, "bottom");
+	filter->abs_cx = (int)obs_data_get_int(settings, "cx");
+	filter->abs_cy = (int)obs_data_get_int(settings, "cy");
+}
+
+static bool relative_clicked(obs_properties_t *props, obs_property_t *p,
+		obs_data_t *settings)
+{
+	bool relative = obs_data_get_bool(settings, "relative");
+
+	obs_property_set_description(obs_properties_get(props, "left"),
+			relative ? obs_module_text("Crop.Left") : "X");
+	obs_property_set_description(obs_properties_get(props, "top"),
+			relative ? obs_module_text("Crop.Top") : "Y");
+
+	obs_property_set_visible(obs_properties_get(props, "right"), relative);
+	obs_property_set_visible(obs_properties_get(props, "bottom"), relative);
+	obs_property_set_visible(obs_properties_get(props, "cx"), !relative);
+	obs_property_set_visible(obs_properties_get(props, "cy"), !relative);
+
+	UNUSED_PARAMETER(p);
+	return true;
+}
+
+static obs_properties_t *crop_filter_properties(void *data)
+{
+	obs_properties_t *props = obs_properties_create();
+
+	obs_property_t *p = obs_properties_add_bool(props, "relative",
+			obs_module_text("Crop.Relative"));
+
+	obs_property_set_modified_callback(p, relative_clicked);
+
+	obs_properties_add_int(props, "left", obs_module_text("Crop.Left"),
+			0, 8192, 1);
+	obs_properties_add_int(props, "top", obs_module_text("Crop.Top"),
+			0, 8192, 1);
+	obs_properties_add_int(props, "right", obs_module_text("Crop.Right"),
+			0, 8192, 1);
+	obs_properties_add_int(props, "bottom", obs_module_text("Crop.Bottom"),
+			0, 8192, 1);
+	obs_properties_add_int(props, "cx", obs_module_text("Crop.Width"),
+			0, 8192, 1);
+	obs_properties_add_int(props, "cy", obs_module_text("Crop.Height"),
+			0, 8192, 1);
+
+	UNUSED_PARAMETER(data);
+	return props;
+}
+
+static void crop_filter_defaults(obs_data_t *settings)
+{
+	obs_data_set_default_bool(settings, "relative", true);
+}
+
+static void calc_crop_dimensions(struct crop_filter_data *filter,
+		struct vec2 *mul_val, struct vec2 *add_val)
+{
+	obs_source_t *target = obs_filter_get_target(filter->context);
+	uint32_t width;
+	uint32_t height;
+	uint32_t total;
+
+	if (!target) {
+		width = 0;
+		height = 0;
+	} else {
+		width = obs_source_get_base_width(target);
+		height = obs_source_get_base_height(target);
+	}
+
+	if (filter->absolute) {
+		uint32_t max_abs_cx = (filter->left + filter->abs_cx);
+		if (max_abs_cx > width) max_abs_cx = width;
+		max_abs_cx -= filter->left;
+
+		total = max_abs_cx < width ? (width - max_abs_cx) : 0;
+	} else {
+		total = filter->left + filter->right;
+	}
+	filter->width = total > width ? 0 : (width - total);
+
+	if (filter->absolute) {
+		uint32_t max_abs_cy = (filter->top + filter->abs_cy);
+		if (max_abs_cy > height) max_abs_cy = height;
+		max_abs_cy -= filter->top;
+
+		total = max_abs_cy < height ? (height - max_abs_cy) : 0;
+	} else {
+		total = filter->top + filter->bottom;
+	}
+	filter->height = total > height ? 0 : (height - total);
+
+	if (width && filter->width) {
+		mul_val->x = (float)filter->width / (float)width;
+		add_val->x = (float)filter->left / (float)width;
+	}
+
+	if (height && filter->height) {
+		mul_val->y = (float)filter->height / (float)height;
+		add_val->y = (float)filter->top / (float)height;
+	}
+}
+
+static void crop_filter_render(void *data, gs_effect_t *effect)
+{
+	struct crop_filter_data *filter = data;
+	struct vec2 mul_val;
+	struct vec2 add_val;
+
+	vec2_zero(&mul_val);
+	vec2_zero(&add_val);
+	calc_crop_dimensions(filter, &mul_val, &add_val);
+
+	obs_source_process_filter_begin(filter->context, GS_RGBA,
+			OBS_NO_DIRECT_RENDERING);
+
+	gs_effect_set_vec2(filter->param_mul, &mul_val);
+	gs_effect_set_vec2(filter->param_add, &add_val);
+
+	obs_source_process_filter_end(filter->context, filter->effect,
+			filter->width, filter->height);
+
+	UNUSED_PARAMETER(effect);
+}
+
+static uint32_t crop_filter_width(void *data)
+{
+	struct crop_filter_data *crop = data;
+	return crop->width;
+}
+
+static uint32_t crop_filter_height(void *data)
+{
+	struct crop_filter_data *crop = data;
+	return crop->height;
+}
+
+struct obs_source_info crop_filter = {
+	.id                            = "crop_filter",
+	.type                          = OBS_SOURCE_TYPE_FILTER,
+	.output_flags                  = OBS_SOURCE_VIDEO,
+	.get_name                      = crop_filter_get_name,
+	.create                        = crop_filter_create,
+	.destroy                       = crop_filter_destroy,
+	.update                        = crop_filter_update,
+	.get_properties                = crop_filter_properties,
+	.get_defaults                  = crop_filter_defaults,
+	.video_render                  = crop_filter_render,
+	.get_width                     = crop_filter_width,
+	.get_height                    = crop_filter_height
+};

plugins/obs-filters/data/crop_filter.effect

+uniform float4x4 ViewProj;
+uniform texture2d image;
+
+uniform float2 mul_val;
+uniform float2 add_val;
+
+sampler_state textureSampler {
+	Filter    = Linear;
+	AddressU  = Clamp;
+	AddressV  = Clamp;
+};
+
+struct VertData {
+	float4 pos : POSITION;
+	float2 uv  : TEXCOORD0;
+};
+
+VertData VSCrop(VertData v_in)
+{
+	VertData vert_out;
+	vert_out.pos = mul(float4(v_in.pos.xyz, 1.0), ViewProj);
+	vert_out.uv  = v_in.uv * mul_val + add_val;
+	return vert_out;
+}
+
+float4 PSCrop(VertData v_in) : TARGET
+{
+	return image.Sample(textureSampler, v_in.uv);
+}
+
+technique Draw
+{
+	pass
+	{
+		vertex_shader = VSCrop(v_in);
+		pixel_shader  = PSCrop(v_in);
+	}
+}

plugins/obs-filters/data/locale/en-US.ini

 MaskFilter="Image Mask/Blend"
 AsyncDelayFilter="Video Delay (Async)"
+CropFilter="Crop"
 DelayMs="Delay (milliseconds)"
 Type="Type"
 MaskBlendType.MaskColor="Alpha Mask (Color Channel)"
@@ -15,3 +16,10 @@ Brightness="Brightness"
 Gamma="Gamma"
 BrowsePath.Images="All Image Files"
 BrowsePath.AllFiles="All Files"
+Crop.Left="Left"
+Crop.Right="Right"
+Crop.Top="Top"
+Crop.Bottom="Bottom"
+Crop.Width="Width"
+Crop.Height="Height"
+Crop.Relative="Relative"

plugins/obs-filters/obs-filters.c

@@ -5,11 +5,13 @@ OBS_DECLARE_MODULE()
 OBS_MODULE_USE_DEFAULT_LOCALE("obs-filters", "en-US")
 
 extern struct obs_source_info mask_filter;
+extern struct obs_source_info crop_filter;
 extern struct obs_source_info async_delay_filter;
 
 bool obs_module_load(void)
 {
 	obs_register_source(&mask_filter);
+	obs_register_source(&crop_filter);
 	obs_register_source(&async_delay_filter);
 	return true;
 }