grid is not really working

5 files changed, 108 insertions, 28 deletions

diff --git a/assets/shaders/grid.frag b/assets/shaders/grid.frag
index 06eebc3..6cf8a7c 100644
--- a/assets/shaders/grid.frag
+++ b/assets/shaders/grid.frag
@@ -2,6 +2,59 @@
 
 out vec4 FragColor;
 
+in float near; //0.01
+in float far; //100
+in vec3 nearPoint;
+in vec3 farPoint;
+in mat4 fragView;
+in mat4 fragProj;
+
+// void main() {
+//     // FragColor = vec4(1.0, 0.0, 0.0, 1.0);
+//     float t = -nearPoint.y / (farPoint.y - nearPoint.y);
+//     if (t > 0) {
+//         FragColor = vec4(1.0, 0.0, 0.0, 1.0);
+//     } else {
+//         FragColor = vec4(0.0);
+//     }
+//     // FragColor = vec4(1.0, 0.0, 0.0, 1.0 * float(t > 0)); // opacity = 1 when t > 0, opacity = 0 otherwise
+// }
+
+vec4 grid(vec3 fragPos3D, float scale, bool drawAxis) {
+    vec2 coord = fragPos3D.xz * scale;
+    vec2 derivative = fwidth(coord);
+    vec2 grid = abs(fract(coord - 0.5) - 0.5) / derivative;
+    float line = min(grid.x, grid.y);
+    float minimumz = min(derivative.y, 1);
+    float minimumx = min(derivative.x, 1);
+    vec4 color = vec4(0.2, 0.2, 0.2, 1.0 - min(line, 1.0));
+    // z axis
+    if(fragPos3D.x > -0.1 * minimumx && fragPos3D.x < 0.1 * minimumx)
+        color.z = 1.0;
+    // x axis
+    if(fragPos3D.z > -0.1 * minimumz && fragPos3D.z < 0.1 * minimumz)
+        color.x = 1.0;
+    return color;
+}
+float computeDepth(vec3 pos) {
+    vec4 clip_space_pos = fragProj * fragView * vec4(pos.xyz, 1.0);
+    return (clip_space_pos.z / clip_space_pos.w);
+}
+float computeLinearDepth(vec3 pos) {
+    vec4 clip_space_pos = fragProj * fragView * vec4(pos.xyz, 1.0);
+    float clip_space_depth = (clip_space_pos.z / clip_space_pos.w) * 2.0 - 1.0; // put back between -1 and 1
+    float linearDepth = (2.0 * near * far) / (far + near - clip_space_depth * (far - near)); // get linear value between 0.01 and 100
+    return linearDepth / far; // normalize
+}
 void main() {
-    FragColor = vec4(1.0, 0.0, 0.0, 1.0);
+    float t = -nearPoint.y / (farPoint.y - nearPoint.y);
+    vec3 fragPos3D = nearPoint + t * (farPoint - nearPoint);
+
+    gl_FragDepth = computeDepth(fragPos3D);
+
+    float linearDepth = computeLinearDepth(fragPos3D);
+    float fading = max(0, (0.5 - linearDepth));
+
+    FragColor = (grid(fragPos3D, 10, true) + grid(fragPos3D, 1, true))* float(t > 0); // adding multiple resolution for the grid
+    FragColor.a *= fading;
 }
\ No newline at end of file
diff --git a/assets/shaders/grid.vert b/assets/shaders/grid.vert
index bdfa477..592cbfc 100644
--- a/assets/shaders/grid.vert
+++ b/assets/shaders/grid.vert
@@ -6,12 +6,37 @@ uniform Camera {
   vec4 viewPos;
 } cam;
 
+out vec3 nearPoint;
+out vec3 farPoint;
+out float near;
+out float far;
+out mat4 fragView;
+out mat4 fragProj;
+
 // Grid position are in xy clipped space
 vec3 gridPlane[6] = vec3[](
     vec3(1, 1, 0), vec3(-1, -1, 0), vec3(-1, 1, 0),
     vec3(-1, -1, 0), vec3(1, 1, 0), vec3(1, -1, 0)
 );
-// normal vertice projection
+
+vec3 UnprojectPoint(float x, float y, float z, mat4 view, mat4 projection) {
+    mat4 viewInv = inverse(view);
+    mat4 projInv = inverse(projection);
+    vec4 unprojectedPoint =  viewInv * projInv * vec4(x, y, z, 1.0);
+    return unprojectedPoint.xyz / unprojectedPoint.w;
+}
+
+// normal vertex projection
 void main() {
-    gl_Position = cam.proj * cam.view * vec4(gridPlane[gl_VertexID].xyz, 1.0);
+    // gl_Position = cam.proj * cam.view * vec4(gridPlane[gl_VertexID].xyz, 1.0);
+    vec3 p = gridPlane[gl_VertexID].xyz;
+    nearPoint = UnprojectPoint(p.x, p.y, -1.0, cam.view, cam.proj).xyz; // unprojecting on the near plane
+    farPoint = UnprojectPoint(p.x, p.y, 1.0, cam.view, cam.proj).xyz; // unprojecting on the far plane
+
+    fragView = cam.view;
+    fragProj = cam.proj;
+    near = 0.01;
+    far = 100.0;
+
+    gl_Position = vec4(p, 1.0); // using directly the clipped coordinates
 }
\ No newline at end of file
diff --git a/examples/game_demo/game_demo.c b/examples/game_demo/game_demo.c
index dfb70d1..e81f6e1 100644
--- a/examples/game_demo/game_demo.c
+++ b/examples/game_demo/game_demo.c
@@ -106,7 +106,7 @@ int main() {
 
     if (draw_debug) {
       // draw the player model with shadows
-      // Render_RenderEntities(render_entities->data, render_entities->len);
+      Render_RenderEntities(render_entities->data, render_entities->len);
       // Render_DrawTerrain();
       Skybox_Draw(&skybox, cam);
     } else {
diff --git a/src/resources/gltf.c b/src/resources/gltf.c
index 41ff9e2..91816d8 100644
--- a/src/resources/gltf.c
+++ b/src/resources/gltf.c
@@ -118,6 +118,24 @@ void load_texcoord_components(Vec2_darray *texcoords, cgltf_accessor *accessor)
   }
 }
 
+void load_joint_index_components(Vec4u_darray *joint_indices, cgltf_accessor *accessor) {
+  TRACE("Load joint indices from accessor");
+  CASSERT(accessor->component_type == cgltf_component_type_r_16u);
+  CASSERT_MSG(accessor->type == cgltf_type_vec4, "Joint indices should be a vec4");
+  Vec4u tmp_joint_index;
+  Vec4 joints_as_floats;
+  for (cgltf_size v = 0; v < accessor->count; ++v) {
+    cgltf_accessor_read_float(accessor, v, &joints_as_floats.x, 4);
+    tmp_joint_index.x = (u32)joints_as_floats.x;
+    tmp_joint_index.y = (u32)joints_as_floats.y;
+    tmp_joint_index.z = (u32)joints_as_floats.z;
+    tmp_joint_index.w = (u32)joints_as_floats.w;
+    printf("Joints affecting vertex %d :  %d %d %d %d\n", v, tmp_joint_index.x, tmp_joint_index.y,
+           tmp_joint_index.z, tmp_joint_index.w);
+    Vec4u_darray_push(joint_indices, tmp_joint_index);
+  }
+}
+
 bool model_load_gltf_str(const char *file_string, const char *filepath, Str8 relative_path,
                          Model *out_model, bool invert_textures_y) {
   TRACE("Load GLTF from string");
@@ -222,25 +240,9 @@ bool model_load_gltf_str(const char *file_string, const char *filepath, Str8 rel
           cgltf_accessor *accessor = attribute.data;
           load_texcoord_components(tmp_uvs, accessor);
         } else if (attribute.type == cgltf_attribute_type_joints) {
-          // FIXME: joints
-          // TRACE("Load joint indices from accessor");
-          // cgltf_accessor *accessor = attribute.data;
-          // assert(accessor->component_type == cgltf_component_type_r_16u);
-          // assert(accessor->type == cgltf_type_vec4);
-          // vec4u joint_indices;
-          // vec4 joints_as_floats;
-          // for (cgltf_size v = 0; v < accessor->count; ++v) {
-          //   cgltf_accessor_read_float(accessor, v, &joints_as_floats.x, 4);
-          //   joint_indices.x = (u32)joints_as_floats.x;
-          //   joint_indices.y = (u32)joints_as_floats.y;
-          //   joint_indices.z = (u32)joints_as_floats.z;
-          //   joint_indices.w = (u32)joints_as_floats.w;
-          //   printf("Joints affecting vertex %d :  %d %d %d %d\n", v, joint_indices.x,
-          //   joint_indices.y,
-          //          joint_indices.z, joint_indices.w);
-          //   vec4u_darray_push(tmp_joint_indices, joint_indices);
-          // }
-
+          TRACE("Load joint indices from accessor");
+          cgltf_accessor *accessor = attribute.data;
+          load_joint_index_components(tmp_joint_indices, accessor);
         } else if (attribute.type == cgltf_attribute_type_weights) {
           // FIXME: weights
           // TRACE("Load joint weights from accessor");
diff --git a/src/systems/grid.c b/src/systems/grid.c
index e095d22..70092e0 100644
--- a/src/systems/grid.c
+++ b/src/systems/grid.c
@@ -8,8 +8,8 @@
 #include "ral_impl.h"
 #include "ral_types.h"
 #include "render.h"
-#include "render_types.h"
 #include "render_scene.h"
+#include "render_types.h"
 #include "shader_layouts.h"
 
 void Grid_Init(Grid_Storage* storage) {
@@ -18,8 +18,9 @@ void Grid_Init(Grid_Storage* storage) {
   Mesh plane_mesh = Mesh_Create(&plane_geo, true);
   storage->plane_vertices = plane_mesh.vertex_buffer;
 
-  u32 indices[6] = { 5,4,3,2,1,0};
-  storage->plane_indices = GPU_BufferCreate(6 * sizeof(u32),BUFFER_INDEX, BUFFER_FLAG_GPU, &indices);
+  u32 indices[6] = { 5, 4, 3, 2, 1, 0 };
+  storage->plane_indices =
+      GPU_BufferCreate(6 * sizeof(u32), BUFFER_INDEX, BUFFER_FLAG_GPU, &indices);
 
   GPU_RenderpassDesc rpass_desc = {
     .default_framebuffer = true,
@@ -63,8 +64,7 @@ void Grid_Draw() {
   Grid_Execute(grid);
 }
 
-void Grid_Execute(Grid_Storage *storage) {
-  WARN("Draw Grid");
+void Grid_Execute(Grid_Storage* storage) {
   RenderScene* scene = Render_GetScene();
   GPU_CmdEncoder* enc = GPU_GetDefaultEncoder();
   GPU_CmdEncoder_BeginRender(enc, storage->renderpass);