diff options
author | Brian Paul <brianp@vmware.com> | 2013-05-03 19:00:07 -0600 |
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committer | Brian Paul <brianp@vmware.com> | 2013-05-03 19:00:07 -0600 |
commit | 3702d2508249bb264ab502c0093dbbc10b0b02fa (patch) | |
tree | a98d030b4114aebda53cb38013aaca22ad378f44 /src | |
parent | a232afdbfbaac156e981f55b8bdeb305026cde84 (diff) |
vbo: create a few utility functions for merging primitives
To be used by following commit.
Reviewed-by: Eric Anholt <eric@anholt.net>
Reviewed-by: José Fonseca <jfonseca@vmware.com>
Diffstat (limited to 'src')
-rw-r--r-- | src/mesa/vbo/vbo.h | 10 | ||||
-rw-r--r-- | src/mesa/vbo/vbo_exec.c | 99 |
2 files changed, 109 insertions, 0 deletions
diff --git a/src/mesa/vbo/vbo.h b/src/mesa/vbo/vbo.h index 9f800d87ad5..08c67d67d43 100644 --- a/src/mesa/vbo/vbo.h +++ b/src/mesa/vbo/vbo.h @@ -33,6 +33,7 @@ #ifndef _VBO_H #define _VBO_H +#include <stdbool.h> #include "main/glheader.h" struct gl_client_array; @@ -170,6 +171,15 @@ vbo_count_tessellated_primitives(GLenum mode, GLuint count, GLuint num_instances); void +vbo_try_prim_conversion(struct _mesa_prim *p); + +bool +vbo_can_merge_prims(const struct _mesa_prim *p0, const struct _mesa_prim *p1); + +void +vbo_merge_prims(struct _mesa_prim *p0, const struct _mesa_prim *p1); + +void vbo_sw_primitive_restart(struct gl_context *ctx, const struct _mesa_prim *prim, GLuint nr_prims, diff --git a/src/mesa/vbo/vbo_exec.c b/src/mesa/vbo/vbo_exec.c index 2ff1c149412..c56a14212d5 100644 --- a/src/mesa/vbo/vbo_exec.c +++ b/src/mesa/vbo/vbo_exec.c @@ -157,3 +157,102 @@ vbo_count_tessellated_primitives(GLenum mode, GLuint count, } return num_primitives * num_instances; } + + + +/** + * In some degenarate cases we can improve our ability to merge + * consecutive primitives. For example: + * glBegin(GL_LINE_STRIP); + * glVertex(1); + * glVertex(1); + * glEnd(); + * glBegin(GL_LINE_STRIP); + * glVertex(1); + * glVertex(1); + * glEnd(); + * Can be merged as a GL_LINES prim with four vertices. + * + * This function converts 2-vertex line strips/loops into GL_LINES, etc. + */ +void +vbo_try_prim_conversion(struct _mesa_prim *p) +{ + if (p->mode == GL_LINE_STRIP && p->count == 2) { + /* convert 2-vertex line strip to a separate line */ + p->mode = GL_LINES; + } + else if ((p->mode == GL_TRIANGLE_STRIP || p->mode == GL_TRIANGLE_FAN) + && p->count == 3) { + /* convert 3-vertex tri strip or fan to a separate triangle */ + p->mode = GL_TRIANGLES; + } + + /* Note: we can't convert a 4-vertex quad strip to a separate quad + * because the vertex ordering is different. We'd have to muck + * around in the vertex data to make it work. + */ +} + + +/** + * Helper function for determining if two subsequent glBegin/glEnd + * primitives can be combined. This is only possible for GL_POINTS, + * GL_LINES, GL_TRIANGLES and GL_QUADS. + * If we return true, it means that we can concatenate p1 onto p0 (and + * discard p1). + */ +bool +vbo_can_merge_prims(const struct _mesa_prim *p0, const struct _mesa_prim *p1) +{ + if (!p0->begin || + !p1->begin || + !p0->end || + !p1->end) + return false; + + /* The prim mode must match (ex: both GL_TRIANGLES) */ + if (p0->mode != p1->mode) + return false; + + /* p1's vertices must come right after p0 */ + if (p0->start + p0->count != p1->start) + return false; + + if (p0->basevertex != p1->basevertex || + p0->num_instances != p1->num_instances || + p0->base_instance != p1->base_instance) + return false; + + /* can always merge subsequent GL_POINTS primitives */ + if (p0->mode == GL_POINTS) + return true; + + /* independent lines with no extra vertices */ + if (p0->mode == GL_LINES && p0->count % 2 == 0 && p1->count % 2 == 0) + return true; + + /* independent tris */ + if (p0->mode == GL_TRIANGLES && p0->count % 3 == 0 && p1->count % 3 == 0) + return true; + + /* independent quads */ + if (p0->mode == GL_QUADS && p0->count % 4 == 0 && p1->count % 4 == 0) + return true; + + return false; +} + + +/** + * If we've determined that p0 and p1 can be merged, this function + * concatenates p1 onto p0. + */ +void +vbo_merge_prims(struct _mesa_prim *p0, const struct _mesa_prim *p1) +{ + assert(vbo_can_merge_prims(p0, p1)); + + p0->count += p1->count; + p0->end = p1->end; +} |