Add lens correction filter

dot_config/obs-studio/plugins/filter-fish-lens.lua

@@ -0,0 +1,183 @@
+-- Inspired by Corner Pin effect filter v1.1 by khaver
+
+obs = obslua
+bit = require("bit")
+
+TEXT_FILTER_NAME = 'UnFish/Fish Lens'
+TEXT_FISH_POWER = 'Strength'
+
+SETTING_FISH_POWER = 'fish_power'
+
+source_def = {}
+source_def.id = 'filter-fish-lens'
+source_def.type = obs.OBS_SOURCE_TYPE_FILTER
+source_def.output_flags = bit.bor(obs.OBS_SOURCE_VIDEO)
+
+function set_render_size(filter)
+    target = obs.obs_filter_get_target(filter.context)
+
+    local width, height
+    if target == nil then
+        width = 0
+        height = 0
+    else
+        width = obs.obs_source_get_base_width(target)
+        height = obs.obs_source_get_base_height(target)
+    end
+
+    filter.width = width
+    filter.height = height
+end
+
+source_def.get_name = function()
+    return TEXT_FILTER_NAME
+end
+
+source_def.create = function(settings, source)
+    filter = {}
+    filter.params = {}
+    filter.context = source
+
+    set_render_size(filter)
+
+    obs.obs_enter_graphics()
+    filter.effect = obs.gs_effect_create(shader, nil, nil)
+    if filter.effect ~= nil then
+        filter.params.fish_power = obs.gs_effect_get_param_by_name(filter.effect, 'fish_power')
+        filter.params.texture_width = obs.gs_effect_get_param_by_name(filter.effect, 'texture_width')
+        filter.params.texture_height = obs.gs_effect_get_param_by_name(filter.effect, 'texture_height')
+    end
+    obs.obs_leave_graphics()
+
+    if filter.effect == nil then
+        source_def.destroy(filter)
+        return nil
+    end
+
+    source_def.update(filter, settings)
+    return filter
+end
+
+source_def.destroy = function(filter)
+    if filter.effect ~= nil then
+        obs.obs_enter_graphics()
+        obs.gs_effect_destroy(filter.effect)
+        obs.obs_leave_graphics()
+    end
+end
+
+source_def.get_width = function(filter)
+    return filter.width
+end
+
+source_def.get_height = function(filter)
+    return filter.height
+end
+
+source_def.update = function(filter, settings)
+    filter.fish_power = obs.obs_data_get_double(settings, SETTING_FISH_POWER)
+
+    set_render_size(filter)
+end
+
+source_def.video_render = function(filter, effect)
+    if not obs.obs_source_process_filter_begin(filter.context, obs.GS_RGBA, obs.OBS_NO_DIRECT_RENDERING) then
+        return
+    end
+
+    obs.gs_effect_set_float(filter.params.fish_power, filter.fish_power)
+    obs.gs_effect_set_float(filter.params.texture_width, filter.width)
+    obs.gs_effect_set_float(filter.params.texture_height, filter.height)
+
+    obs.obs_source_process_filter_end(filter.context, filter.effect, filter.width, filter.height)
+end
+
+source_def.get_properties = function(settings)
+    props = obs.obs_properties_create()
+
+    obs.obs_properties_add_float_slider(props, SETTING_FISH_POWER, TEXT_FISH_POWER, -1.0, 2.0, 0.001)
+
+    return props
+end
+
+source_def.get_defaults = function(settings)
+    obs.obs_data_set_default_double(settings, SETTING_FISH_POWER, -0.18)
+end
+
+source_def.video_tick = function(filter, seconds)
+    set_render_size(filter)
+end
+
+function script_description()
+    return "Adds new video effect filter named '" .. TEXT_FILTER_NAME .. "' to imitate lens distortion"
+end
+
+function script_load(settings)
+    obs.obs_register_source(source_def)
+end
+
+shader = [[
+// Adaptation by Suslik V
+// Based on the Sharpness shader of OBS Studio v27.0.0,
+// And the https://github.com/Oncorporation/obs-shaderfilter/
+
+uniform float4x4 ViewProj;
+uniform texture2d image;
+
+uniform float fish_power;
+uniform float texture_width;
+uniform float texture_height;
+
+sampler_state def_sampler {
+    Filter   = Linear;
+    AddressU = Clamp;
+    AddressV = Clamp;
+};
+
+struct VertData {
+    float4 pos : POSITION;
+    float2 uv  : TEXCOORD0;
+};
+
+VertData VSDefault(VertData v_in)
+{
+    VertData vert_out;
+    vert_out.pos = mul(float4(v_in.pos.xyz, 1.0), ViewProj);
+    vert_out.uv  = v_in.uv;
+    return vert_out;
+}
+
+float4 PSDrawBare(VertData v_in) : TARGET
+{
+    int center_x_percent = 50;
+    int center_y_percent = 50;
+    float power = fish_power;
+    float2 uv_pixel_interval;
+    uv_pixel_interval.x = 1.0 / texture_width;
+    uv_pixel_interval.y = 1.0 / texture_height;
+    float2 center_pos = float2(center_x_percent * .01, center_y_percent * .01);
+    float2 uv = v_in.uv;
+    if (power >= 0.0001) {
+        float b = sqrt(dot(center_pos, center_pos));
+        uv = center_pos  + normalize(v_in.uv - center_pos) * tan(distance(center_pos, v_in.uv) * power) * b / tan( b * power);
+    } else if (power <= -0.0001) {
+        float b;
+        if (uv_pixel_interval.x < uv_pixel_interval.y){
+            b = center_pos.x;
+        } else {
+            b = center_pos.y;
+        }
+        uv = center_pos  + normalize(v_in.uv - center_pos) * atan(distance(center_pos, v_in.uv) * -power * 10.0) * b / atan(-power * b * 10.0);
+    }
+    return image.Sample(def_sampler, uv);
+}
+
+technique Draw
+{
+    pass
+    {
+        vertex_shader = VSDefault(v_in);
+        pixel_shader  = PSDrawBare(v_in);
+    }
+}
+]]