gl_shader_gen: Implement fragment lighting fresnel effect.

This commit is contained in:
bunnei 2015-11-23 20:26:09 -05:00
parent 0e67c21c9e
commit c37de30cfc
3 changed files with 38 additions and 9 deletions

View file

@ -97,7 +97,13 @@ struct PicaShaderConfig {
res.lighting.lut_d1.type = (Pica::Regs::LightingLutInput)regs.lighting.lut_input.d1.Value();
res.lighting.lut_d1.scale = regs.lighting.lut_scale.GetScale(regs.lighting.lut_scale.d1);
res.lighting.lut_fr.enable = regs.lighting.lut_enable_fr == 0;
res.lighting.lut_fr.abs_input = regs.lighting.abs_lut_input.fr == 0;
res.lighting.lut_fr.type = (Pica::Regs::LightingLutInput)regs.lighting.lut_input.fr.Value();
res.lighting.lut_fr.scale = regs.lighting.lut_scale.GetScale(regs.lighting.lut_scale.fr);
res.lighting.config = regs.lighting.config;
res.lighting.fresnel_selector = regs.lighting.fresnel_selector;
res.lighting.clamp_highlights = regs.lighting.clamp_highlights != 0;
return res;
@ -134,6 +140,7 @@ struct PicaShaderConfig {
unsigned src_num = 0;
bool clamp_highlights = false;
Pica::Regs::LightingConfig config = Pica::Regs::LightingConfig::Config0;
Pica::Regs::LightingFresnelSelector fresnel_selector = Pica::Regs::LightingFresnelSelector::None;
struct {
bool enable = false;

View file

@ -321,8 +321,8 @@ static void WriteTevStage(std::string& out, const PicaShaderConfig& config, unsi
/// Writes the code to emulate fragment lighting
static void WriteLighting(std::string& out, const PicaShaderConfig& config) {
// Define lighting globals
out += "vec3 diffuse_sum = vec3(0.0);\n";
out += "vec3 specular_sum = vec3(0.0);\n";
out += "vec4 diffuse_sum = vec4(0.0, 0.0, 0.0, 1.0);\n";
out += "vec4 specular_sum = vec4(0.0, 0.0, 0.0, 1.0);\n";
out += "vec3 light_vector = vec3(0.0);\n";
// Convert interpolated quaternion to a GL fragment normal
@ -402,9 +402,6 @@ static void WriteLighting(std::string& out, const PicaShaderConfig& config) {
dist_atten = GetLutValue((Regs::LightingSampler)lut_num, lut_index);
}
// Compute primary fragment color (diffuse lighting) function
out += "diffuse_sum += ((" + light_src + ".diffuse * " + dot_product + ") + " + light_src + ".ambient) * " + dist_atten + ";\n";
// If enabled, clamp specular component if lighting result is negative
std::string clamp_highlights = config.lighting.clamp_highlights ? "(dot(light_vector, normal) <= 0.0 ? 0.0 : 1.0)" : "1.0";
@ -426,14 +423,34 @@ static void WriteLighting(std::string& out, const PicaShaderConfig& config) {
}
std::string specular_1 = "(" + d1_lut_value + " * " + light_src + ".specular_1)";
// Fresnel
if (config.lighting.lut_fr.enable && Pica::Regs::IsLightingSamplerSupported(config.lighting.config, Pica::Regs::LightingSampler::Fresnel)) {
// Lookup fresnel LUT value
std::string fr_lut_index = GetLutIndex(light_config.num, config.lighting.lut_fr.type, config.lighting.lut_fr.abs_input);
std::string fr_lut_value = "(" + std::to_string(config.lighting.lut_fr.scale) + " * " + GetLutValue(Regs::LightingSampler::Fresnel, fr_lut_index) + ")";
// Enabled for difffuse lighting alpha component
if (config.lighting.fresnel_selector == Pica::Regs::LightingFresnelSelector::PrimaryAlpha ||
config.lighting.fresnel_selector == Pica::Regs::LightingFresnelSelector::BothAlpha)
out += "diffuse_sum.a *= " + fr_lut_value + ";\n";
// Enabled for the specular lighting alpha component
if (config.lighting.fresnel_selector == Pica::Regs::LightingFresnelSelector::SecondaryAlpha ||
config.lighting.fresnel_selector == Pica::Regs::LightingFresnelSelector::BothAlpha)
out += "specular_sum.a *= " + fr_lut_value + ";\n";
}
// Compute primary fragment color (diffuse lighting) function
out += "diffuse_sum.rgb += ((" + light_src + ".diffuse * " + dot_product + ") + " + light_src + ".ambient) * " + dist_atten + ";\n";
// Compute secondary fragment color (specular lighting) function
out += "specular_sum += (" + specular_0 + " + " + specular_1 + ") * " + clamp_highlights + " * " + dist_atten + ";\n";
out += "specular_sum.rgb += (" + specular_0 + " + " + specular_1 + ") * " + clamp_highlights + " * " + dist_atten + ";\n";
}
// Sum final lighting result
out += "diffuse_sum += lighting_global_ambient;\n";
out += "primary_fragment_color = vec4(clamp(diffuse_sum, vec3(0.0), vec3(1.0)), 1.0);\n";
out += "secondary_fragment_color = vec4(clamp(specular_sum, vec3(0.0), vec3(1.0)), 1.0);\n";
out += "diffuse_sum.rgb += lighting_global_ambient;\n";
out += "primary_fragment_color = clamp(diffuse_sum, vec4(0.0), vec4(1.0));\n";
out += "secondary_fragment_color = clamp(specular_sum, vec4(0.0), vec4(1.0));\n";
}
std::string GenerateFragmentShader(const PicaShaderConfig& config) {