Default Shader Parts

Shader parts are used by Model-Based Rendering and Text Shaders. This file contains an index of parts by priority, and the source of each shader part.

Vertex Part Priorities

How Ren'Py uses vertex part priorities:

  • Priority 0 sets up gl_Position.

  • Priority 10 is used to capture gl_Position in virtual or drawable coordinates before adjustment.

  • Priorities 20-80 adjust gl_Position in virtual or drawable coordinates.

  • Priority 90 is used to capture gl_Position in virtual or drawable coordinates after adjustment.

  • Priority 100 transforms gl_Position to viewport coordinates.

  • Priority 200 stores more information in the variables passed to the fragment shader, without touching gl_Position.

In order:

Fragment Part Priorities

How Ren'Py uses fragment part priorities:

  • Priority 200 determines an original color and stores it in the fragment output (fragment_color in GLSL ES 3.00 or gl_FragColor in GLSL ES 1.00).

  • Priority 300 multiplies that color with a second texture.

  • Priority 325 stores alpha before the text shaders adjust it.

  • Priority 350 applies text shaders that adjust alpha.

  • Priority 375 can undo part of the effect of these text shaders.

  • Priority 400 adjusts the color, applying Transform and displayable-based changes.

  • Priority 450 converts color to alpha.

  • Priority 500 adjusts the alpha channel, applying Transform and displayable-based changes.

In order:

renpy.alpha

Variables:

uniform float u_renpy_alpha;
uniform float u_renpy_over;

Fragment shader (priority 500):

fragment_color *= u_renpy_alpha * vec4(1.0, 1.0, 1.0, u_renpy_over);

renpy.alpha_mask

Variables:

uniform sampler2D tex0;
uniform sampler2D tex1;
in vec2 a_tex_coord;
out vec2 v_tex_coord;

Vertex shader (priority 200):

v_tex_coord = a_tex_coord;

Fragment shader (priority 500):

// The mask is in the red channel, and the result is premultiplied.
float l_renpy_alpha_mask_mask = texture(tex1, v_tex_coord).r;

fragment_color = vec4(texture(tex0, v_tex_coord).rgb * l_renpy_alpha_mask_mask, l_renpy_alpha_mask_mask);

renpy.blur

Variables:

uniform sampler2D tex0;
in vec2 a_tex_coord;
out vec2 v_tex_coord;
uniform float u_renpy_blur_log2;

Vertex shader (priority 200):

v_tex_coord = a_tex_coord;

Fragment shader (priority 200):

float l_renpy_blur_norm = 0.0;

for (int l_renpy_blur_i = -5; l_renpy_blur_i <= 0; l_renpy_blur_i++) {
    float l_renpy_blur_distance = u_renpy_blur_log2 - float(l_renpy_blur_i);
    l_renpy_blur_norm += exp(-0.5 * l_renpy_blur_distance * l_renpy_blur_distance);
}

vec4 l_renpy_blur_acc = l_renpy_blur_norm * texture(tex0, v_tex_coord, 0.0);

for (int l_renpy_blur_i = 1; l_renpy_blur_i < 14; l_renpy_blur_i++) {
    float l_renpy_blur_level = float(l_renpy_blur_i);

    if (l_renpy_blur_level >= u_renpy_blur_log2 + 5.0) {
        break;
    }

    float l_renpy_blur_distance = u_renpy_blur_log2 - l_renpy_blur_level;
    float l_renpy_blur_weight = exp(-0.5 * l_renpy_blur_distance * l_renpy_blur_distance);

    l_renpy_blur_acc += l_renpy_blur_weight * texture(tex0, v_tex_coord, l_renpy_blur_level);
    l_renpy_blur_norm += l_renpy_blur_weight;
}

if (l_renpy_blur_norm > 0.0) {
    fragment_color = l_renpy_blur_acc / l_renpy_blur_norm;
} else {
    fragment_color = texture(tex0, v_tex_coord, 0.0);
}

renpy.dissolve

Variables:

uniform float u_lod_bias;
uniform sampler2D tex0;
uniform sampler2D tex1;
uniform float u_renpy_dissolve;
in vec2 a_tex_coord;
out vec2 v_tex_coord;

Vertex shader (priority 200):

v_tex_coord = a_tex_coord;

Fragment shader (priority 200):

fragment_color = mix(
    texture(tex0, v_tex_coord, u_lod_bias),
    texture(tex1, v_tex_coord, u_lod_bias),
    u_renpy_dissolve);

renpy.geometry

Variables:

uniform mat4 u_transform;
in vec4 a_position;

Vertex shader (priority 0):

gl_Position = a_position;

Vertex shader (priority 100):

gl_Position = u_transform * gl_Position;

renpy.imagedissolve

Variables:

uniform float u_lod_bias;
uniform sampler2D tex0;
uniform sampler2D tex1;
uniform sampler2D tex2;
uniform float u_renpy_dissolve_offset;
uniform float u_renpy_dissolve_multiplier;
in vec2 a_tex_coord;
out vec2 v_tex_coord;

Vertex shader (priority 200):

v_tex_coord = a_tex_coord;

Fragment shader (priority 200):

float l_renpy_imagedissolve_done = clamp(
    (texture(tex0, v_tex_coord, u_lod_bias).a + u_renpy_dissolve_offset) * u_renpy_dissolve_multiplier,
    0.0, 1.0);

fragment_color = mix(
    texture(tex1, v_tex_coord, u_lod_bias),
    texture(tex2, v_tex_coord, u_lod_bias),
    l_renpy_imagedissolve_done);

renpy.mask

Variables:

uniform float u_lod_bias;
uniform sampler2D tex0;
uniform sampler2D tex1;
uniform float u_renpy_mask_multiplier;
uniform float u_renpy_mask_offset;
in vec2 a_tex_coord;
out vec2 v_tex_coord;

Vertex shader (priority 200):

v_tex_coord = a_tex_coord;

Fragment shader (priority 200):

float l_renpy_mask_mask = texture(tex1, v_tex_coord, u_lod_bias).a;

fragment_color = texture(tex0, v_tex_coord, u_lod_bias)
    * (l_renpy_mask_mask * u_renpy_mask_multiplier + u_renpy_mask_offset);

renpy.matrixcolor

Variables:

uniform mat4 u_renpy_matrixcolor;

Fragment shader (priority 400):

fragment_color = u_renpy_matrixcolor * fragment_color;

renpy.movie_yuv

Variables:

uniform sampler2D tex0;
uniform sampler2D tex1;
uniform float u_movie_yuv_full_range;
uniform float u_movie_yuv_bt709;
in vec2 a_tex_coord;
out vec2 v_tex_coord;

Vertex shader (priority 200):

v_tex_coord = a_tex_coord;

Fragment shader (priority 200):

// Rec. 601 used for standard definition.
const mat3 l_renpy_movie_yuv_bt601 = mat3(
    1.0,    1.0,       1.0,
    0.0,   -0.344136,  1.772,
    1.402, -0.714136,  0.0);

// Rec. 709 used for high definition.
const mat3 l_renpy_movie_yuv_bt709 = mat3(
    1.0,    1.0,       1.0,
    0.0,   -0.187324,  1.8556,
    1.5748, -0.468124,  0.0);

float l_renpy_movie_yuv_luma = texture(tex0, v_tex_coord).r;
vec2 l_renpy_movie_yuv_chroma = texture(tex1, v_tex_coord).ra - 0.5;

if (u_movie_yuv_full_range < 0.5) {
    // Studio swing puts luma in 16-235 and chroma in 16-240, of 0-255.
    l_renpy_movie_yuv_luma = (l_renpy_movie_yuv_luma - 16.0 / 255.0) * (255.0 / 219.0);
    l_renpy_movie_yuv_chroma *= 255.0 / 224.0;
}

vec3 l_renpy_movie_yuv_yuv = vec3(l_renpy_movie_yuv_luma, l_renpy_movie_yuv_chroma);
vec3 l_renpy_movie_yuv_rgb = (u_movie_yuv_bt709 > 0.5) ? l_renpy_movie_yuv_bt709 * l_renpy_movie_yuv_yuv : l_renpy_movie_yuv_bt601 * l_renpy_movie_yuv_yuv;

fragment_color = vec4(clamp(l_renpy_movie_yuv_rgb, 0.0, 1.0), 1.0);

renpy.red_to_alpha

Fragment shader (priority 450):

fragment_color = vec4(fragment_color.r);

renpy.solid

Variables:

uniform vec4 u_renpy_solid_color;

Fragment shader (priority 200):

fragment_color = u_renpy_solid_color;

renpy.texture

Variables:

uniform float u_lod_bias;
uniform sampler2D tex0;
in vec2 a_tex_coord;
out vec2 v_tex_coord;

Vertex shader (priority 200):

v_tex_coord = a_tex_coord;

Fragment shader (priority 200):

fragment_color = texture(tex0, v_tex_coord, u_lod_bias);

textshader.dissolve

Variables:

uniform float u_textshader_dissolve_duration;
uniform float u_text_slow_duration;
uniform float u_text_slow_time;
in float a_text_time;
out float v_text_time;

Vertex shader (priority 200):

v_text_time = a_text_time;

Fragment shader (priority 350):

float l_textshader_dissolve_duration = u_textshader_dissolve_duration * u_text_slow_duration;
float l_textshader_dissolve_done = step(v_text_time, u_text_slow_time);

if (l_textshader_dissolve_duration > 0.0) {
    l_textshader_dissolve_done = clamp((u_text_slow_time - v_text_time) / l_textshader_dissolve_duration, 0.0, 1.0);
}

fragment_color *= l_textshader_dissolve_done;

textshader.flip

Variables:

uniform float u_textshader_flip_duration;
uniform float u_text_slow_duration;
uniform float u_text_slow_time;
in vec2 a_text_center;
in float a_text_min_time;

Vertex shader (priority 20):

float l_textshader_flip_duration = u_textshader_flip_duration * u_text_slow_duration;
float l_textshader_flip_done = step(a_text_min_time, u_text_slow_time);

if (l_textshader_flip_duration > 0.0) {
    l_textshader_flip_done = clamp((u_text_slow_time - a_text_min_time) / l_textshader_flip_duration, 0.0, 1.0);
}

gl_Position.x = mix(2.0 * a_text_center.x - gl_Position.x, gl_Position.x, l_textshader_flip_done);

textshader.jitter

Variables:

uniform vec2 u_textshader_jitter_jitter;
uniform vec4 u_random;
uniform float u_text_to_drawable;

Vertex shader (priority 30):

vec2 l_textshader_jitter_jitter = u_textshader_jitter_jitter * u_text_to_drawable;
gl_Position.xy += l_textshader_jitter_jitter * u_random.xy - l_textshader_jitter_jitter / 2.0;

textshader.linetexture

Variables:

uniform sampler2D u_textshader_linetexture_texture;
uniform vec2 u_textshader_linetexture_scale;
uniform vec2 u_textshader_linetexture_texture_res;

uniform float u_text_to_virtual;
uniform float u_text_main;

in vec2 a_text_center;
out vec2 v_textshader_linetexture_coord;

Vertex shader (priority 10):

v_textshader_linetexture_coord = vec2(gl_Position.x, gl_Position.y - a_text_center.y) / u_textshader_linetexture_scale * u_text_to_virtual / u_textshader_linetexture_texture_res;
v_textshader_linetexture_coord.y += 0.5;

Fragment shader (priority 300):

if (u_text_main == 1.0) {
    fragment_color *= texture(u_textshader_linetexture_texture, v_textshader_linetexture_coord);
}

textshader.offset

Variables:

uniform vec2 u_textshader_offset_offset;
uniform float u_text_to_drawable;

Vertex shader (priority 35):

gl_Position.xy += u_textshader_offset_offset * u_text_to_drawable;

textshader.slowalpha

Variables:

uniform float u_textshader_slowalpha_alpha;

Fragment shader (priority 325):

vec4 l_textshader_slowalpha_color = fragment_color;

Fragment shader (priority 375):

fragment_color = mix(fragment_color, l_textshader_slowalpha_color, u_textshader_slowalpha_alpha);

textshader.texture

Variables:

uniform sampler2D u_textshader_texture_texture;
uniform vec2 u_textshader_texture_texture_res;

uniform float u_text_to_virtual;
uniform float u_text_main;
out vec2 v_textshader_texture_coord;

Vertex shader (priority 10):

v_textshader_texture_coord = u_text_to_virtual * gl_Position.xy / u_textshader_texture_texture_res;

Fragment shader (priority 300):

if (u_text_main == 1.0) {
    fragment_color *= texture(u_textshader_texture_texture, v_textshader_texture_coord);
}

textshader.typewriter

Variables:

uniform float u_text_slow_time;
in float a_text_min_time;
out float v_text_min_time;

Vertex shader (priority 200):

v_text_min_time = a_text_min_time;

Fragment shader (priority 350):

fragment_color *= step(v_text_min_time, u_text_slow_time);

textshader.wave

Variables:

uniform float u_textshader_wave_amplitude;
uniform float u_textshader_wave_frequency;
uniform float u_textshader_wave_wavelength;

uniform float u_time;
uniform float u_text_to_drawable;
in float a_text_index;

Vertex shader (priority 40):

const float l_textshader_wave_two_pi = 6.28318530718;

float l_textshader_wave_phase = a_text_index / u_textshader_wave_wavelength + u_time * u_textshader_wave_frequency;
gl_Position.y += cos(l_textshader_wave_two_pi * l_textshader_wave_phase) * u_textshader_wave_amplitude * u_text_to_drawable;

textshader.zoom

Variables:

uniform float u_textshader_zoom_zoom;
uniform float u_textshader_zoom_duration;
uniform float u_text_slow_duration;
uniform float u_text_slow_time;
in vec2 a_text_center;
in float a_text_min_time;

Vertex shader (priority 25):

float l_textshader_zoom_duration = u_textshader_zoom_duration * u_text_slow_duration;

if (l_textshader_zoom_duration > 0.0) {
    float l_textshader_zoom_done = clamp((u_text_slow_time - a_text_min_time) / l_textshader_zoom_duration, 0.0, 1.0);
    gl_Position.xy = mix(a_text_center + (gl_Position.xy - a_text_center) * u_textshader_zoom_zoom, gl_Position.xy, l_textshader_zoom_done);
}