mutter/tests/conform/test-backface-culling.c
Neil Roberts 8fba6265d2 Port the backface culling test
This ports the backface culling conformance test to work without
Clutter.

Reviewed-by: Robert Bragg <robert@linux.intel.com>
2011-09-19 16:40:07 +01:00

309 lines
8.9 KiB
C

#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 4
/* Size to actually render the texture at */
#define TEXTURE_RENDER_SIZE 32
typedef struct _TestState
{
CoglFramebuffer *fb;
CoglHandle texture;
CoglFramebuffer *offscreen;
CoglHandle offscreen_tex;
int width, height;
} TestState;
static gboolean
validate_part (int xnum, int ynum, gboolean shown)
{
guchar *pixels, *p;
gboolean ret = TRUE;
pixels = g_malloc0 ((TEXTURE_RENDER_SIZE - TEST_INSET * 2)
* (TEXTURE_RENDER_SIZE - TEST_INSET * 2) * 4);
/* Read the appropriate part but skip out a few pixels around the
edges */
cogl_read_pixels (xnum * TEXTURE_RENDER_SIZE + TEST_INSET,
ynum * TEXTURE_RENDER_SIZE + TEST_INSET,
TEXTURE_RENDER_SIZE - TEST_INSET * 2,
TEXTURE_RENDER_SIZE - TEST_INSET * 2,
COGL_READ_PIXELS_COLOR_BUFFER,
COGL_PIXEL_FORMAT_RGBA_8888_PRE,
pixels);
/* Make sure every pixel is the appropriate color */
for (p = pixels;
p < pixels + ((TEXTURE_RENDER_SIZE - TEST_INSET * 2)
* (TEXTURE_RENDER_SIZE - TEST_INSET * 2));
p += 4)
{
if (p[0] != (shown ? 255 : 0))
ret = FALSE;
if (p[1] != 0)
ret = FALSE;
if (p[2] != 0)
ret = FALSE;
}
g_free (pixels);
return ret;
}
static void
paint_test_backface_culling (TestState *state)
{
int i;
CoglPipeline *pipeline = cogl_pipeline_new ();
CoglColor clear_color;
cogl_ortho (0, state->width, /* left, right */
state->height, 0, /* bottom, top */
-1, 100 /* z near, far */);
cogl_color_init_from_4ub (&clear_color, 0x00, 0x00, 0x00, 0xff);
cogl_clear (&clear_color, COGL_BUFFER_BIT_COLOR | COGL_BUFFER_BIT_STENCIL);
cogl_pipeline_set_layer_texture (pipeline, 0, state->texture);
cogl_pipeline_set_layer_filters (pipeline, 0,
COGL_PIPELINE_FILTER_NEAREST,
COGL_PIPELINE_FILTER_NEAREST);
cogl_set_backface_culling_enabled (TRUE);
cogl_push_matrix ();
/* Render the scene twice - once with backface culling enabled and
once without. The second time is translated so that it is below
the first */
for (i = 0; i < 2; i++)
{
float x1 = 0, x2, y1 = 0, y2 = (float)(TEXTURE_RENDER_SIZE);
CoglTextureVertex verts[4];
cogl_set_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);
/* Draw a regular rectangle (this should always show) */
cogl_set_source_color4f (1.0, 0, 0, 1.0);
cogl_rectangle (x1, y1, x2, y2);
/* The second time round draw beneath the first with backface
culling disabled */
cogl_translate (0, TEXTURE_RENDER_SIZE, 0);
cogl_set_backface_culling_enabled (FALSE);
}
cogl_object_unref (pipeline);
cogl_pop_matrix ();
}
static void
validate_result (int y_offset)
{
/* Front-facing texture */
g_assert (validate_part (0, y_offset + 0, TRUE));
/* Front-facing texture with flipped tex coords */
g_assert (validate_part (1, y_offset + 0, TRUE));
/* Back-facing texture */
g_assert (validate_part (2, y_offset + 0, FALSE));
/* Front-facing texture polygon */
g_assert (validate_part (3, y_offset + 0, TRUE));
/* Back-facing texture polygon */
g_assert (validate_part (4, y_offset + 0, FALSE));
/* Regular rectangle */
g_assert (validate_part (5, y_offset + 0, TRUE));
/* Backface culling disabled - everything should be shown */
/* Front-facing texture */
g_assert (validate_part (0, y_offset + 1, TRUE));
/* Front-facing texture with flipped tex coords */
g_assert (validate_part (1, y_offset + 1, TRUE));
/* Back-facing texture */
g_assert (validate_part (2, y_offset + 1, TRUE));
/* Front-facing texture polygon */
g_assert (validate_part (3, y_offset + 1, TRUE));
/* Back-facing texture polygon */
g_assert (validate_part (4, y_offset + 1, TRUE));
/* Regular rectangle */
g_assert (validate_part (5, y_offset + 1, TRUE));
}
static void
paint (TestState *state)
{
float stage_viewport[4];
CoglMatrix stage_projection;
CoglMatrix stage_modelview;
paint_test_backface_culling (state);
/*
* 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
*/
cogl_get_viewport (stage_viewport);
cogl_get_projection_matrix (&stage_projection);
cogl_get_modelview_matrix (&stage_modelview);
cogl_push_framebuffer (state->offscreen);
cogl_set_viewport (stage_viewport[0],
stage_viewport[1],
stage_viewport[2],
stage_viewport[3]);
cogl_set_projection_matrix (&stage_projection);
cogl_set_modelview_matrix (&stage_modelview);
paint_test_backface_culling (state);
cogl_pop_framebuffer ();
/* Incase we want feedback of what was drawn offscreen we draw it
* to the stage... */
cogl_set_source_texture (state->offscreen_tex);
cogl_rectangle (0, TEXTURE_RENDER_SIZE * 2,
stage_viewport[2],
stage_viewport[3] + TEXTURE_RENDER_SIZE * 2);
validate_result (0);
validate_result (2);
cogl_framebuffer_swap_buffers (state->fb);
}
static CoglHandle
make_texture (void)
{
guchar *tex_data, *p;
CoglHandle 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 = cogl_texture_new_from_data (TEXTURE_SIZE,
TEXTURE_SIZE,
COGL_TEXTURE_NO_ATLAS,
COGL_PIXEL_FORMAT_RGBA_8888,
COGL_PIXEL_FORMAT_ANY,
TEXTURE_SIZE * 4,
tex_data);
g_free (tex_data);
return tex;
}
void
test_cogl_backface_culling (TestUtilsGTestFixture *fixture,
void *data)
{
TestUtilsSharedState *shared_state = data;
TestState state;
CoglHandle tex;
state.fb = shared_state->fb;
state.width = cogl_framebuffer_get_width (shared_state->fb);
state.height = cogl_framebuffer_get_height (shared_state->fb);
state.offscreen = COGL_INVALID_HANDLE;
state.texture = make_texture ();
tex = cogl_texture_new_with_size (state.width, state.height,
COGL_TEXTURE_NO_SLICING,
COGL_PIXEL_FORMAT_ANY); /* internal fmt */
state.offscreen = cogl_offscreen_new_to_texture (tex);
state.offscreen_tex = tex;
paint (&state);
cogl_object_unref (state.offscreen);
cogl_handle_unref (state.offscreen_tex);
cogl_handle_unref (state.texture);
if (g_test_verbose ())
g_print ("OK\n");
}