1 files changed, 122 insertions, 0 deletions
diff --git a/source/blender/draw/intern/draw_shader.c b/source/blender/draw/intern/draw_shader.c
new file mode 100644
index 00000000000..9c756065353
--- /dev/null
+++ b/source/blender/draw/intern/draw_shader.c
@@ -0,0 +1,122 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * Copyright 2020, Blender Foundation.
+ */
+
+/** \file
+ * \ingroup draw_engine
+ */
+
+#include "DRW_render.h"
+
+#include "BLI_dynstr.h"
+#include "BLI_string_utils.h"
+
+#include "GPU_batch.h"
+#include "GPU_index_buffer.h"
+#include "GPU_vertex_buffer.h"
+
+#include "draw_shader.h"
+
+extern char datatoc_common_hair_lib_glsl[];
+
+extern char datatoc_common_hair_refine_vert_glsl[];
+extern char datatoc_common_hair_refine_comp_glsl[];
+extern char datatoc_gpu_shader_3D_smooth_color_frag_glsl[];
+
+static struct {
+  struct GPUShader *hair_refine_sh[PART_REFINE_MAX_SHADER];
+} e_data = {{NULL}};
+
+/* -------------------------------------------------------------------- */
+/** \name Hair refinement
+ * \{ */
+
+static GPUShader *hair_refine_shader_compute_create(ParticleRefineShader UNUSED(refinement))
+{
+  GPUShader *sh = NULL;
+  sh = GPU_shader_create_compute(datatoc_common_hair_refine_comp_glsl,
+                                 datatoc_common_hair_lib_glsl,
+                                 "#define HAIR_PHASE_SUBDIV\n",
+                                 __func__);
+  return sh;
+}
+
+static GPUShader *hair_refine_shader_transform_feedback_create(
+    ParticleRefineShader UNUSED(refinement))
+{
+  GPUShader *sh = NULL;
+
+  char *shader_src = BLI_string_joinN(datatoc_common_hair_lib_glsl,
+                                      datatoc_common_hair_refine_vert_glsl);
+  const char *var_names[1] = {"finalColor"};
+  sh = DRW_shader_create_with_transform_feedback(
+      shader_src, NULL, "#define HAIR_PHASE_SUBDIV\n", GPU_SHADER_TFB_POINTS, var_names, 1);
+  MEM_freeN(shader_src);
+
+  return sh;
+}
+
+static GPUShader *hair_refine_shader_transform_feedback_workaround_create(
+    ParticleRefineShader UNUSED(refinement))
+{
+  GPUShader *sh = NULL;
+
+  char *shader_src = BLI_string_joinN(datatoc_common_hair_lib_glsl,
+                                      datatoc_common_hair_refine_vert_glsl);
+  sh = DRW_shader_create(shader_src,
+                         NULL,
+                         datatoc_gpu_shader_3D_smooth_color_frag_glsl,
+                         "#define blender_srgb_to_framebuffer_space(a) a\n"
+                         "#define HAIR_PHASE_SUBDIV\n"
+                         "#define TF_WORKAROUND\n");
+  MEM_freeN(shader_src);
+
+  return sh;
+}
+
+GPUShader *DRW_shader_hair_refine_get(ParticleRefineShader refinement,
+                                      eParticleRefineShaderType sh_type)
+{
+  if (e_data.hair_refine_sh[refinement] == NULL) {
+    GPUShader *sh = NULL;
+    switch (sh_type) {
+      case PART_REFINE_SHADER_COMPUTE:
+        sh = hair_refine_shader_compute_create(refinement);
+        break;
+      case PART_REFINE_SHADER_TRANSFORM_FEEDBACK:
+        sh = hair_refine_shader_transform_feedback_create(refinement);
+        break;
+      case PART_REFINE_SHADER_TRANSFORM_FEEDBACK_WORKAROUND:
+        sh = hair_refine_shader_transform_feedback_workaround_create(refinement);
+        break;
+      default:
+        BLI_assert(!"Incorrect shader type");
+    }
+    e_data.hair_refine_sh[refinement] = sh;
+  }
+
+  return e_data.hair_refine_sh[refinement];
+}
+
+/** \} */
+
+void DRW_shaders_free(void)
+{
+  for (int i = 0; i < PART_REFINE_MAX_SHADER; i++) {
+    DRW_SHADER_FREE_SAFE(e_data.hair_refine_sh[i]);
+  }
+}