basic creature model

[blobs.git] / src / graphics / shader.cpp

diff --git a/src/graphics/shader.cpp b/src/graphics/shader.cpp
index 573e90c3731d6f25fce4cc3a7a9e4ae7b98d3d97..c7b5fdd326e58bcd26651aaf0e925206daf877ef 100644 (file)
--- a/src/graphics/shader.cpp
+++ b/src/graphics/shader.cpp
@@ -1,3 +1,4 @@
+#include "CreatureSkin.hpp"
 #include "PlanetSurface.hpp"
 #include "Program.hpp"
 #include "Shader.hpp"
@@ -447,5 +448,127 @@ void SunSurface::Draw() const noexcept {
        vao.DrawTriangles(36);
 }
 
+
+constexpr int CreatureSkin::MAX_LIGHTS;
+
+CreatureSkin::CreatureSkin()
+: prog() {
+       prog.LoadShader(
+               GL_VERTEX_SHADER,
+               "#version 330 core\n"
+
+               "layout(location = 0) in vec3 vtx_position;\n"
+               "layout(location = 1) in vec3 vtx_normal;\n"
+               "layout(location = 2) in vec3 vtx_tex_uv;\n"
+
+               "uniform mat4 M;\n"
+               "uniform mat4 MV;\n"
+               "uniform mat4 MVP;\n"
+
+               "out vec3 vtx_viewspace;\n"
+               "out vec3 frag_tex_uv;\n"
+               "out vec3 normal;\n"
+
+               "void main() {\n"
+                       "gl_Position = MVP * vec4(vtx_position, 1);\n"
+                       "vtx_viewspace = (MV * vec4(vtx_position, 1)).xyz;\n"
+                       "normal = normalize((MV * vec4(vtx_normal, 0)).xyz);\n"
+                       "frag_tex_uv = vtx_tex_uv;\n"
+               "}\n"
+       );
+       prog.LoadShader(
+               GL_FRAGMENT_SHADER,
+               "#version 330 core\n"
+
+               "struct LightSource {\n"
+                       "vec3 position;\n"
+                       "vec3 color;\n"
+                       "float strength;\n"
+               "};\n"
+
+               "in vec3 vtx_viewspace;\n"
+               "in vec3 frag_tex_uv;\n"
+               "in vec3 normal;\n"
+
+               "uniform sampler2DArray tex_sampler;\n"
+               "uniform int num_lights;\n"
+               "uniform LightSource light[8];\n"
+
+               "out vec3 color;\n"
+
+               "void main() {\n"
+                       "vec3 tex_color = texture(tex_sampler, frag_tex_uv).rgb;\n"
+                       "vec3 total_light = tex_color * vec3(0.01, 0.01, 0.01);\n"
+                       "for (int i = 0; i < num_lights; ++i) {\n"
+                               "vec3 to_light = light[i].position - vtx_viewspace;\n"
+                               "float distance = length(to_light) + length(vtx_viewspace);\n"
+                               "vec3 light_dir = normalize(to_light);\n"
+                               "float attenuation = light[i].strength / (distance * distance);\n"
+                               "vec3 diffuse = attenuation * max(0.0, dot(normal, light_dir)) * light[i].color * tex_color;\n"
+                               "vec3 view_dir = vec3(0.0, 0.0, 1.0);\n"
+                               "vec3 specular = vec3(0.0, 0.0, 0.0);\n"
+                               "if (dot(normal, light_dir) >= 0.0) {\n"
+                                       "attenuation * light[i].color * pow(max(0.0, dot(reflect(-light_dir, normal), view_dir)), 25.0);\n"
+                               "}\n"
+                               "total_light = total_light + diffuse + specular;\n"
+                       "}\n"
+                       "color = total_light;\n"
+               "}\n"
+       );
+       prog.Link();
+       if (!prog.Linked()) {
+               prog.Log(std::cerr);
+               throw std::runtime_error("link program");
+       }
+       m_handle = prog.UniformLocation("M");
+       mv_handle = prog.UniformLocation("MV");
+       mvp_handle = prog.UniformLocation("MVP");
+       sampler_handle = prog.UniformLocation("tex_sampler");
+       num_lights_handle = prog.UniformLocation("num_lights");
+       for (int i = 0; i < MAX_LIGHTS; ++i) {
+               light_handle[3 * i + 0]  = prog.UniformLocation("light[" + std::to_string(i) + "].position");
+               light_handle[3 * i + 1]  = prog.UniformLocation("light[" + std::to_string(i) + "].color");
+               light_handle[3 * i + 2]  = prog.UniformLocation("light[" + std::to_string(i) + "].strength");
+       }
+}
+
+CreatureSkin::~CreatureSkin() {
+}
+
+void CreatureSkin::Activate() noexcept {
+       prog.Use();
+       glEnable(GL_DEPTH_TEST);
+       glDepthFunc(GL_LESS);
+       glEnable(GL_CULL_FACE);
+       glDisable(GL_BLEND);
+}
+
+void CreatureSkin::SetMVP(const glm::mat4 &mm, const glm::mat4 &vv, const glm::mat4 &pp) noexcept {
+       m = mm;
+       v = vv;
+       p = pp;
+       mv = v * m;
+       mvp = p * mv;
+       prog.Uniform(m_handle, m);
+       prog.Uniform(mv_handle, mv);
+       prog.Uniform(mvp_handle, mvp);
+}
+
+void CreatureSkin::SetTexture(ArrayTexture &tex) noexcept {
+       glActiveTexture(GL_TEXTURE0);
+       tex.Bind();
+       prog.Uniform(sampler_handle, GLint(0));
+}
+
+void CreatureSkin::SetLight(int n, const glm::vec3 &pos, const glm::vec3 &color, float strength) noexcept {
+       prog.Uniform(light_handle[3 * n + 0], pos);
+       prog.Uniform(light_handle[3 * n + 1], color);
+       prog.Uniform(light_handle[3 * n + 2], strength);
+}
+
+void CreatureSkin::SetNumLights(int n) noexcept {
+       prog.Uniform(num_lights_handle, std::min(MAX_LIGHTS, n));
+}
+
 }
 }