postfx subpixel

This commit is contained in:
2026-03-21 14:41:51 +01:00
parent e9fc2e8fa0
commit 06457654f4
5 changed files with 51 additions and 12 deletions

View File

@@ -31,9 +31,10 @@ out vec4 FragColor;
// Uniforms
uniform sampler2D Texture;
uniform vec2 TextureSize;
uniform float uVignette; // 0 = sin viñeta, 1 = máxima
uniform float uScanlines; // 0 = desactivadas, 1 = plenas
uniform float uChroma; // 0 = sin aberración, 1 = máxima
uniform float uVignette; // 0 = sin viñeta, 1 = máxima
uniform float uScanlines; // 0 = desactivadas, 1 = plenas
uniform float uChroma; // 0 = sin aberración, 1 = máxima
uniform float uOutputHeight; // altura del viewport en pixels de pantalla
#if defined(CURVATURE)
vec2 Distort(vec2 coord)
@@ -103,8 +104,20 @@ void main()
#else
float tempY = floor(texcoordInPixels.y) + 0.5;
float yCoord = tempY / TextureSize.y;
// Scanline en espacio de pantalla (subpíxel)
float scaleY = uOutputHeight / TextureSize.y;
float screenY = vTexCoord.y * uOutputHeight;
float posInRow = mod(screenY, scaleY);
float scanLineDY = posInRow / scaleY - 0.5;
float localFilterWidth = 1.0 / scaleY;
float scanLineWeight = CalcScanLineWeight(scanLineDY);
scanLineWeight += CalcScanLineWeight(scanLineDY - localFilterWidth);
scanLineWeight += CalcScanLineWeight(scanLineDY + localFilterWidth);
scanLineWeight *= 0.3333333;
// Phosphor blur en espacio textura (sin cambios)
float dy = texcoordInPixels.y - tempY;
float scanLineWeight = CalcScanLine(dy);
float signY = sign(dy);
dy = dy * dy;
dy = dy * dy;

View File

@@ -34,9 +34,10 @@ out vec4 FragColor;
// Uniforms
uniform sampler2D Texture;
uniform vec2 TextureSize;
uniform float uVignette; // 0 = sin viñeta, 1 = máxima
uniform float uScanlines; // 0 = desactivadas, 1 = plenas
uniform float uChroma; // 0 = sin aberración, 1 = máxima
uniform float uVignette; // 0 = sin viñeta, 1 = máxima
uniform float uScanlines; // 0 = desactivadas, 1 = plenas
uniform float uChroma; // 0 = sin aberración, 1 = máxima
uniform float uOutputHeight; // altura del viewport en pixels de pantalla
#if defined(CURVATURE)
vec2 Distort(vec2 coord)
@@ -106,8 +107,20 @@ void main()
#else
float tempY = floor(texcoordInPixels.y) + 0.5;
float yCoord = tempY / TextureSize.y;
// Scanline en espacio de pantalla (subpíxel)
float scaleY = uOutputHeight / TextureSize.y;
float screenY = vTexCoord.y * uOutputHeight;
float posInRow = mod(screenY, scaleY);
float scanLineDY = posInRow / scaleY - 0.5;
float localFilterWidth = 1.0 / scaleY;
float scanLineWeight = CalcScanLineWeight(scanLineDY);
scanLineWeight += CalcScanLineWeight(scanLineDY - localFilterWidth);
scanLineWeight += CalcScanLineWeight(scanLineDY + localFilterWidth);
scanLineWeight *= 0.3333333;
// Phosphor blur en espacio textura (sin cambios)
float dy = texcoordInPixels.y - tempY;
float scanLineWeight = CalcScanLine(dy);
float signY = sign(dy);
dy = dy * dy;
dy = dy * dy;

View File

@@ -338,9 +338,10 @@ auto OpenGLShader::init(SDL_Window* window,
}
// Uniforms PostFX
vignette_location_ = glGetUniformLocation(program_id_, "uVignette");
scanlines_location_ = glGetUniformLocation(program_id_, "uScanlines");
chroma_location_ = glGetUniformLocation(program_id_, "uChroma");
vignette_location_ = glGetUniformLocation(program_id_, "uVignette");
scanlines_location_ = glGetUniformLocation(program_id_, "uScanlines");
chroma_location_ = glGetUniformLocation(program_id_, "uChroma");
output_height_location_ = glGetUniformLocation(program_id_, "uOutputHeight");
if (vignette_location_ != -1) { glUniform1f(vignette_location_, postfx_vignette_); }
if (scanlines_location_ != -1) { glUniform1f(scanlines_location_, postfx_scanlines_); }
if (chroma_location_ != -1) { glUniform1f(chroma_location_, postfx_chroma_); }
@@ -446,6 +447,10 @@ void OpenGLShader::render() {
glViewport(viewport_x, viewport_y, viewport_w, viewport_h);
checkGLError("glViewport");
if (output_height_location_ != -1) {
glUniform1f(output_height_location_, static_cast<float>(viewport_h));
}
// Dibujar quad usando VAO
glBindVertexArray(vao_);
glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, nullptr);

View File

@@ -59,6 +59,7 @@ class OpenGLShader : public ShaderBackend {
GLint vignette_location_ = -1;
GLint scanlines_location_ = -1;
GLint chroma_location_ = -1;
GLint output_height_location_ = -1;
// Valores cacheados de PostFX
float postfx_vignette_ = 0.6F;

View File

@@ -61,7 +61,12 @@ fragment float4 postfx_fs(PostVOut in [[stage_in]],
color.b = scene.sample(samp, in.uv - float2( ca, 0.0)).b;
color.a = scene.sample(samp, in.uv).a;
float scan = 0.85 + 0.15 * sin(in.uv.y * 3.14159265 * u.screen_height);
float texHeight = float(scene.get_height());
float scaleY = u.screen_height / texHeight;
float screenY = in.uv.y * u.screen_height;
float posInRow = fmod(screenY, scaleY);
float scanLineDY = posInRow / scaleY - 0.5;
float scan = max(1.0 - scanLineDY * scanLineDY * 6.0, 0.12) * 3.5;
color.rgb *= mix(1.0, scan, u.scanline_strength);
float2 d = in.uv - float2(0.5, 0.5);
@@ -312,6 +317,8 @@ void SDL3GPUShader::render() {
return;
}
uniforms_.screen_height = static_cast<float>(sh);
// ---- Render pass: PostFX → swapchain ----
SDL_GPUColorTargetInfo color_target = {};
color_target.texture = swapchain;