[Bf-blender-cvs] [94e14a2] blender2.8: OpenGL: new built-in shaders for mesh edges
Mike Erwin
noreply at git.blender.org
Tue Oct 25 09:21:42 CEST 2016
Commit: 94e14a2c43f60ce13bda9375d3fd6c07e964d896
Author: Mike Erwin
Date: Tue Oct 25 03:19:10 2016 -0400
Branches: blender2.8
https://developer.blender.org/rB94e14a2c43f60ce13bda9375d3fd6c07e964d896
OpenGL: new built-in shaders for mesh edges
===================================================================
M source/blender/gpu/CMakeLists.txt
M source/blender/gpu/GPU_shader.h
M source/blender/gpu/intern/gpu_shader.c
A source/blender/gpu/shaders/gpu_shader_edges_front_back_ortho_vert.glsl
A source/blender/gpu/shaders/gpu_shader_edges_front_back_persp_vert.glsl
===================================================================
diff --git a/source/blender/gpu/CMakeLists.txt b/source/blender/gpu/CMakeLists.txt
index 0bb383a..17bf77f 100644
--- a/source/blender/gpu/CMakeLists.txt
+++ b/source/blender/gpu/CMakeLists.txt
@@ -157,6 +157,8 @@ data_to_c_simple(shaders/gpu_shader_2D_point_uniform_size_smooth_vert.glsl SRC)
data_to_c_simple(shaders/gpu_shader_2D_point_uniform_size_outline_smooth_vert.glsl SRC)
data_to_c_simple(shaders/gpu_shader_2D_point_uniform_size_varying_color_outline_smooth_vert.glsl SRC)
+data_to_c_simple(shaders/gpu_shader_edges_front_back_persp_vert.glsl SRC)
+data_to_c_simple(shaders/gpu_shader_edges_front_back_ortho_vert.glsl SRC)
data_to_c_simple(shaders/gpu_shader_text_vert.glsl SRC)
data_to_c_simple(shaders/gpu_shader_text_frag.glsl SRC)
diff --git a/source/blender/gpu/GPU_shader.h b/source/blender/gpu/GPU_shader.h
index e19588a..aead5ba 100644
--- a/source/blender/gpu/GPU_shader.h
+++ b/source/blender/gpu/GPU_shader.h
@@ -90,7 +90,10 @@ typedef enum GPUBuiltinShader {
GPU_SHADER_SMOKE = 2,
GPU_SHADER_SMOKE_FIRE = 3,
+ /* specialized drawing */
GPU_SHADER_TEXT,
+ GPU_SHADER_EDGES_FRONT_BACK_PERSP,
+ GPU_SHADER_EDGES_FRONT_BACK_ORTHO,
/* for simple 2D drawing */
GPU_SHADER_2D_UNIFORM_COLOR,
diff --git a/source/blender/gpu/intern/gpu_shader.c b/source/blender/gpu/intern/gpu_shader.c
index 21fd538..6b6cdfb 100644
--- a/source/blender/gpu/intern/gpu_shader.c
+++ b/source/blender/gpu/intern/gpu_shader.c
@@ -77,6 +77,8 @@ extern char datatoc_gpu_shader_2D_point_uniform_size_smooth_vert_glsl[];
extern char datatoc_gpu_shader_2D_point_uniform_size_outline_smooth_vert_glsl[];
extern char datatoc_gpu_shader_2D_point_uniform_size_varying_color_outline_smooth_vert_glsl[];
+extern char datatoc_gpu_shader_edges_front_back_persp_vert_glsl[];
+extern char datatoc_gpu_shader_edges_front_back_ortho_vert_glsl[];
extern char datatoc_gpu_shader_text_vert_glsl[];
extern char datatoc_gpu_shader_text_frag_glsl[];
@@ -105,8 +107,10 @@ static struct GPUShadersGlobal {
GPUShader *smoke_fire;
/* cache for shader fx. Those can exist in combinations so store them here */
GPUShader *fx_shaders[MAX_FX_SHADERS * 2];
- /* for drawing text */
+ /* specialized drawing */
GPUShader *text;
+ GPUShader *edges_front_back_persp;
+ GPUShader *edges_front_back_ortho;
/* for drawing images */
GPUShader *image_modulate_alpha_3D;
GPUShader *image_rect_modulate_alpha_3D;
@@ -656,6 +660,22 @@ GPUShader *GPU_shader_get_builtin_shader(GPUBuiltinShader shader)
NULL, NULL, NULL, 0, 0, 0);
retval = GG.shaders.text;
break;
+ case GPU_SHADER_EDGES_FRONT_BACK_PERSP:
+ if (!GG.shaders.edges_front_back_persp)
+ GG.shaders.edges_front_back_persp = GPU_shader_create(
+ datatoc_gpu_shader_edges_front_back_persp_vert_glsl,
+ datatoc_gpu_shader_flat_color_frag_glsl,
+ NULL, NULL, NULL, 0, 0, 0);
+ retval = GG.shaders.edges_front_back_persp;
+ break;
+ case GPU_SHADER_EDGES_FRONT_BACK_ORTHO:
+ if (!GG.shaders.edges_front_back_ortho)
+ GG.shaders.edges_front_back_ortho = GPU_shader_create(
+ datatoc_gpu_shader_edges_front_back_ortho_vert_glsl,
+ datatoc_gpu_shader_flat_color_frag_glsl,
+ NULL, NULL, NULL, 0, 0, 0);
+ retval = GG.shaders.edges_front_back_ortho;
+ break;
case GPU_SHADER_3D_IMAGE_MODULATE_ALPHA:
if (!GG.shaders.image_modulate_alpha_3D)
GG.shaders.image_modulate_alpha_3D = GPU_shader_create(
@@ -938,6 +958,16 @@ void GPU_shader_free_builtin_shaders(void)
GG.shaders.text = NULL;
}
+ if (GG.shaders.edges_front_back_persp) {
+ GPU_shader_free(GG.shaders.edges_front_back_persp);
+ GG.shaders.edges_front_back_persp = NULL;
+ }
+
+ if (GG.shaders.edges_front_back_ortho) {
+ GPU_shader_free(GG.shaders.edges_front_back_ortho);
+ GG.shaders.edges_front_back_ortho = NULL;
+ }
+
if (GG.shaders.image_modulate_alpha_3D) {
GPU_shader_free(GG.shaders.image_modulate_alpha_3D);
GG.shaders.image_modulate_alpha_3D = NULL;
diff --git a/source/blender/gpu/shaders/gpu_shader_edges_front_back_ortho_vert.glsl b/source/blender/gpu/shaders/gpu_shader_edges_front_back_ortho_vert.glsl
new file mode 100755
index 0000000..0648bf1
--- /dev/null
+++ b/source/blender/gpu/shaders/gpu_shader_edges_front_back_ortho_vert.glsl
@@ -0,0 +1,64 @@
+
+// Draw "fancy" wireframe, displaying front-facing, back-facing and
+// silhouette lines differently.
+// Mike Erwin, April 2015
+
+uniform bool drawFront = true;
+uniform bool drawBack = true;
+uniform bool drawSilhouette = true;
+
+uniform vec4 frontColor;
+uniform vec4 backColor;
+uniform vec4 silhouetteColor;
+
+uniform vec4 eye; // direction we are looking
+
+uniform mat4 ModelViewProjectionMatrix;
+
+#if __VERSION__ == 120
+ attribute vec3 pos;
+
+ // normals of faces this edge joins (object coords)
+ attribute vec3 N1;
+ attribute vec3 N2;
+
+ flat varying vec4 finalColor;
+#else
+ in vec3 pos;
+
+ // normals of faces this edge joins (object coords)
+ in vec3 N1;
+ in vec3 N2;
+
+ flat out vec4 finalColor;
+#endif
+
+// TODO: in float angle; // [-pi .. +pi], + peak, 0 flat, - valley
+
+// to discard an entire line, set both endpoints to nowhere
+// and it won't produce any fragments
+const vec4 nowhere = vec4(vec3(0.0), 1.0);
+
+void main()
+{
+ bool face_1_front = dot(N1, eye) > 0.0;
+ bool face_2_front = dot(N2, eye) > 0.0;
+
+ vec4 position = ModelViewProjectionMatrix * vec4(pos, 1.0);
+
+ if (face_1_front && face_2_front) {
+ // front-facing edge
+ gl_Position = drawFront ? position : nowhere;
+ finalColor = frontColor;
+ }
+ else if (face_1_front || face_2_front) {
+ // exactly one face is front-facing, silhouette edge
+ gl_Position = drawSilhouette ? position : nowhere;
+ finalColor = silhouetteColor;
+ }
+ else {
+ // back-facing edge
+ gl_Position = drawBack ? position : nowhere;
+ finalColor = backColor;
+ }
+}
diff --git a/source/blender/gpu/shaders/gpu_shader_edges_front_back_persp_vert.glsl b/source/blender/gpu/shaders/gpu_shader_edges_front_back_persp_vert.glsl
new file mode 100755
index 0000000..baf69c3
--- /dev/null
+++ b/source/blender/gpu/shaders/gpu_shader_edges_front_back_persp_vert.glsl
@@ -0,0 +1,78 @@
+
+// Draw "fancy" wireframe, displaying front-facing, back-facing and
+// silhouette lines differently.
+// Mike Erwin, April 2015
+
+// After working with this shader a while, convinced we should make
+// separate shaders for perpective & ortho. (Oct 2016)
+
+// This shader is an imperfect stepping stone until all platforms are
+// ready for geometry shaders.
+
+// Due to perspective, the line segment's endpoints might disagree on
+// whether the adjacent faces are front facing. Need to use a geometry
+// shader or pass in an extra position attribute (the other endpoint)
+// to do this properly.
+
+uniform bool drawFront = true;
+uniform bool drawBack = true;
+uniform bool drawSilhouette = true;
+
+uniform vec4 frontColor;
+uniform vec4 backColor;
+uniform vec4 silhouetteColor;
+
+uniform mat4 ModelViewMatrix;
+uniform mat4 ModelViewProjectionMatrix;
+uniform mat3 NormalMatrix;
+
+#if __VERSION__ == 120
+ attribute vec3 pos;
+
+ // normals of faces this edge joins (object coords)
+ attribute vec3 N1;
+ attribute vec3 N2;
+
+ flat varying vec4 finalColor;
+#else
+ in vec3 pos;
+
+ // normals of faces this edge joins (object coords)
+ in vec3 N1;
+ in vec3 N2;
+
+ flat out vec4 finalColor;
+#endif
+
+// TODO: in float angle; // [-pi .. +pi], + peak, 0 flat, - valley
+
+// to discard an entire line, set its color to invisible
+// (must have GL_BLEND enabled, or discard in fragment shader)
+const vec4 invisible = vec4(0.0);
+
+bool front(vec3 N)
+{
+ vec4 xformed = ModelViewMatrix * vec4(pos, 1.0);
+ return dot(NormalMatrix * N, normalize(-xformed.xyz)) > 0.0;
+}
+
+void main()
+{
+ bool face_1_front = front(N1);
+ bool face_2_front = front(N2);
+
+ gl_Position = ModelViewProjectionMatrix * vec4(pos, 1.0);
+
+ if (face_1_front && face_2_front) {
+ // front-facing edge
+ finalColor = drawFront ? frontColor : invisible;
+ }
+ else if (face_1_front || face_2_front) {
+ // exactly one face is front-facing, silhouette edge
+ finalColor = drawSilhouette ? silhouetteColor : invisible;
+ }
+ else {
+ // back-facing edge
+ finalColor = drawBack ? backColor : invisible;
+ }
+}
More information about the Bf-blender-cvs
mailing list