mutter/cogl/tests/conform/test-backface-culling.c
2016-04-22 16:44:31 +02:00

312 lines
9.3 KiB
C

#define COGL_VERSION_MIN_REQUIRED COGL_VERSION_1_0
#include <cogl/cogl.h>
#include <string.h>
#include "test-utils.h"
/* Size the texture so that it is just off a power of two to encourage
it so use software tiling when NPOTs aren't available */
#define TEXTURE_SIZE 257
/* Amount of pixels to skip off the top, bottom, left and right of the
texture when reading back the stage */
#define TEST_INSET 2
/* Size to actually render the texture at */
#define TEXTURE_RENDER_SIZE 8
typedef struct _TestState
{
CoglTexture *texture;
CoglFramebuffer *offscreen;
CoglTexture *offscreen_tex;
int width, height;
} TestState;
static void
validate_part (CoglFramebuffer *framebuffer,
int xnum, int ynum, CoglBool shown)
{
test_utils_check_region (framebuffer,
xnum * TEXTURE_RENDER_SIZE + TEST_INSET,
ynum * TEXTURE_RENDER_SIZE + TEST_INSET,
TEXTURE_RENDER_SIZE - TEST_INSET * 2,
TEXTURE_RENDER_SIZE - TEST_INSET * 2,
shown ? 0xff0000ff : 0x000000ff);
}
/* We draw everything 16 times. The draw number is used as a bitmask
to test all of the combinations of enabling legacy state, both
winding orders and all four culling modes */
#define USE_LEGACY_STATE(draw_num) (((draw_num) & 0x01) >> 0)
#define FRONT_WINDING(draw_num) (((draw_num) & 0x02) >> 1)
#define CULL_FACE_MODE(draw_num) (((draw_num) & 0x0c) >> 2)
static void
paint_test_backface_culling (TestState *state,
CoglFramebuffer *framebuffer)
{
int draw_num;
CoglPipeline *base_pipeline = cogl_pipeline_new (test_ctx);
cogl_framebuffer_orthographic (framebuffer,
0, 0,
state->width,
state->height,
-1,
100);
cogl_framebuffer_clear4f (framebuffer,
COGL_BUFFER_BIT_COLOR | COGL_BUFFER_BIT_STENCIL,
0, 0, 0, 1);
cogl_pipeline_set_layer_texture (base_pipeline, 0, state->texture);
cogl_pipeline_set_layer_filters (base_pipeline, 0,
COGL_PIPELINE_FILTER_NEAREST,
COGL_PIPELINE_FILTER_NEAREST);
cogl_push_framebuffer (framebuffer);
/* Render the scene sixteen times to test all of the combinations of
cull face mode, legacy state and winding orders */
for (draw_num = 0; draw_num < 16; draw_num++)
{
float x1 = 0, x2, y1 = 0, y2 = (float)(TEXTURE_RENDER_SIZE);
CoglTextureVertex verts[4];
CoglPipeline *pipeline;
cogl_push_matrix ();
cogl_translate (0, TEXTURE_RENDER_SIZE * draw_num, 0);
pipeline = cogl_pipeline_copy (base_pipeline);
cogl_set_backface_culling_enabled (USE_LEGACY_STATE (draw_num));
cogl_pipeline_set_front_face_winding (pipeline, FRONT_WINDING (draw_num));
cogl_pipeline_set_cull_face_mode (pipeline, CULL_FACE_MODE (draw_num));
cogl_push_source (pipeline);
memset (verts, 0, sizeof (verts));
x2 = x1 + (float)(TEXTURE_RENDER_SIZE);
/* Draw a front-facing texture */
cogl_rectangle (x1, y1, x2, y2);
x1 = x2;
x2 = x1 + (float)(TEXTURE_RENDER_SIZE);
/* Draw a front-facing texture with flipped texcoords */
cogl_rectangle_with_texture_coords (x1, y1, x2, y2,
1.0, 0.0, 0.0, 1.0);
x1 = x2;
x2 = x1 + (float)(TEXTURE_RENDER_SIZE);
/* Draw a back-facing texture */
cogl_rectangle (x2, y1, x1, y2);
x1 = x2;
x2 = x1 + (float)(TEXTURE_RENDER_SIZE);
/* If the texture is sliced then cogl_polygon doesn't work so
we'll just use a solid color instead */
if (cogl_texture_is_sliced (state->texture))
cogl_set_source_color4ub (255, 0, 0, 255);
/* Draw a front-facing polygon */
verts[0].x = x1; verts[0].y = y2;
verts[1].x = x2; verts[1].y = y2;
verts[2].x = x2; verts[2].y = y1;
verts[3].x = x1; verts[3].y = y1;
verts[0].tx = 0; verts[0].ty = 0;
verts[1].tx = 1.0; verts[1].ty = 0;
verts[2].tx = 1.0; verts[2].ty = 1.0;
verts[3].tx = 0; verts[3].ty = 1.0;
cogl_polygon (verts, 4, FALSE);
x1 = x2;
x2 = x1 + (float)(TEXTURE_RENDER_SIZE);
/* Draw a back-facing polygon */
verts[0].x = x1; verts[0].y = y1;
verts[1].x = x2; verts[1].y = y1;
verts[2].x = x2; verts[2].y = y2;
verts[3].x = x1; verts[3].y = y2;
verts[0].tx = 0; verts[0].ty = 0;
verts[1].tx = 1.0; verts[1].ty = 0;
verts[2].tx = 1.0; verts[2].ty = 1.0;
verts[3].tx = 0; verts[3].ty = 1.0;
cogl_polygon (verts, 4, FALSE);
x1 = x2;
x2 = x1 + (float)(TEXTURE_RENDER_SIZE);
cogl_pop_matrix ();
cogl_pop_source ();
cogl_object_unref (pipeline);
}
cogl_pop_framebuffer ();
cogl_object_unref (base_pipeline);
}
static void
validate_result (CoglFramebuffer *framebuffer, int y_offset)
{
int draw_num;
for (draw_num = 0; draw_num < 16; draw_num++)
{
CoglBool cull_front, cull_back;
CoglPipelineCullFaceMode cull_mode;
if (USE_LEGACY_STATE (draw_num))
cull_mode = COGL_PIPELINE_CULL_FACE_MODE_BACK;
else
cull_mode = CULL_FACE_MODE (draw_num);
switch (cull_mode)
{
case COGL_PIPELINE_CULL_FACE_MODE_NONE:
cull_front = FALSE;
cull_back = FALSE;
break;
case COGL_PIPELINE_CULL_FACE_MODE_FRONT:
cull_front = TRUE;
cull_back = FALSE;
break;
case COGL_PIPELINE_CULL_FACE_MODE_BACK:
cull_front = FALSE;
cull_back = TRUE;
break;
case COGL_PIPELINE_CULL_FACE_MODE_BOTH:
cull_front = TRUE;
cull_back = TRUE;
break;
}
if (FRONT_WINDING (draw_num) == COGL_WINDING_CLOCKWISE)
{
CoglBool tmp = cull_front;
cull_front = cull_back;
cull_back = tmp;
}
/* Front-facing texture */
validate_part (framebuffer,
0, y_offset + draw_num, !cull_front);
/* Front-facing texture with flipped tex coords */
validate_part (framebuffer,
1, y_offset + draw_num, !cull_front);
/* Back-facing texture */
validate_part (framebuffer,
2, y_offset + draw_num, !cull_back);
/* Front-facing texture polygon */
validate_part (framebuffer,
3, y_offset + draw_num, !cull_front);
/* Back-facing texture polygon */
validate_part (framebuffer,
4, y_offset + draw_num, !cull_back);
}
}
static void
paint (TestState *state)
{
CoglPipeline *pipeline;
paint_test_backface_culling (state, test_fb);
/*
* Now repeat the test but rendered to an offscreen
* framebuffer. Note that by default the conformance tests are
* always run to an offscreen buffer but we might as well have this
* check anyway in case it is being run with COGL_TEST_ONSCREEN=1
*/
paint_test_backface_culling (state, state->offscreen);
/* Copy the result of the offscreen rendering for validation and
* also so we can have visual feedback. */
pipeline = cogl_pipeline_new (test_ctx);
cogl_pipeline_set_layer_texture (pipeline, 0, state->offscreen_tex);
cogl_framebuffer_draw_rectangle (test_fb,
pipeline,
0, TEXTURE_RENDER_SIZE * 16,
state->width,
state->height + TEXTURE_RENDER_SIZE * 16);
cogl_object_unref (pipeline);
validate_result (test_fb, 0);
validate_result (test_fb, 16);
}
static CoglTexture *
make_texture (void)
{
guchar *tex_data, *p;
CoglTexture *tex;
tex_data = g_malloc (TEXTURE_SIZE * TEXTURE_SIZE * 4);
for (p = tex_data + TEXTURE_SIZE * TEXTURE_SIZE * 4; p > tex_data;)
{
*(--p) = 255;
*(--p) = 0;
*(--p) = 0;
*(--p) = 255;
}
tex = test_utils_texture_new_from_data (test_ctx,
TEXTURE_SIZE,
TEXTURE_SIZE,
TEST_UTILS_TEXTURE_NO_ATLAS,
COGL_PIXEL_FORMAT_RGBA_8888,
TEXTURE_SIZE * 4,
tex_data);
g_free (tex_data);
return tex;
}
void
test_backface_culling (void)
{
TestState state;
CoglTexture *tex;
state.width = cogl_framebuffer_get_width (test_fb);
state.height = cogl_framebuffer_get_height (test_fb);
state.offscreen = NULL;
state.texture = make_texture ();
tex = test_utils_texture_new_with_size (test_ctx,
state.width, state.height,
TEST_UTILS_TEXTURE_NO_SLICING,
COGL_TEXTURE_COMPONENTS_RGBA);
state.offscreen = cogl_offscreen_new_with_texture (tex);
state.offscreen_tex = tex;
paint (&state);
cogl_object_unref (state.offscreen);
cogl_object_unref (state.offscreen_tex);
cogl_object_unref (state.texture);
if (cogl_test_verbose ())
g_print ("OK\n");
}