swrast.c

Mesa is an open-source implementation of the OpenGL specification - a system for rendering interacti

/*
 * Copyright (C) 2008 George Sapountzis <[e-mail]>
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
 * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

/*
 * DRI software rasterizer
 *
 * This is the mesa swrast module packaged into a DRI driver structure.
 *
 * The front-buffer is allocated by the loader. The loader provides read/write
 * callbacks for access to the front-buffer. The driver uses a scratch row for
 * front-buffer rendering to avoid repeated calls to the loader.
 *
 * The back-buffer is allocated by the driver and is private.
 */

#include "context.h"
#include "extensions.h"
#include "framebuffer.h"
#include "imports.h"
#include "renderbuffer.h"
#include "swrast/swrast.h"
#include "swrast_setup/swrast_setup.h"
#include "tnl/tnl.h"
#include "tnl/t_context.h"
#include "tnl/t_pipeline.h"
#include "vbo/vbo.h"
#include "drivers/common/driverfuncs.h"
#include "utils.h"

#include "swrast_priv.h"


#define need_GL_VERSION_1_3
#define need_GL_VERSION_1_4
#define need_GL_VERSION_1_5
#define need_GL_VERSION_2_0
#define need_GL_VERSION_2_1

/* sw extensions for imaging */
#define need_GL_EXT_blend_color
#define need_GL_EXT_blend_minmax
#define need_GL_EXT_convolution
#define need_GL_EXT_histogram
#define need_GL_SGI_color_table

/* sw extensions not associated with some GL version */
#define need_GL_ARB_shader_objects
#define need_GL_ARB_vertex_program
#define need_GL_APPLE_vertex_array_object
#define need_GL_ATI_fragment_shader
#define need_GL_EXT_depth_bounds_test
#define need_GL_EXT_framebuffer_object
#define need_GL_EXT_framebuffer_blit
#define need_GL_EXT_gpu_program_parameters
#define need_GL_EXT_paletted_texture
#define need_GL_IBM_multimode_draw_arrays
#define need_GL_MESA_resize_buffers
#define need_GL_NV_vertex_program
#define need_GL_NV_fragment_program

#include "extension_helper.h"

const struct dri_extension card_extensions[] =
{
    { "GL_VERSION_1_3",			GL_VERSION_1_3_functions },
    { "GL_VERSION_1_4",			GL_VERSION_1_4_functions },
    { "GL_VERSION_1_5",			GL_VERSION_1_5_functions },
    { "GL_VERSION_2_0",			GL_VERSION_2_0_functions },
    { "GL_VERSION_2_1",			GL_VERSION_2_1_functions },

    { "GL_EXT_blend_color",		GL_EXT_blend_color_functions },
    { "GL_EXT_blend_minmax",		GL_EXT_blend_minmax_functions },
    { "GL_EXT_convolution",		GL_EXT_convolution_functions },
    { "GL_EXT_histogram",		GL_EXT_histogram_functions },
    { "GL_SGI_color_table",		GL_SGI_color_table_functions },

    { "GL_ARB_shader_objects",		GL_ARB_shader_objects_functions },
    { "GL_ARB_vertex_program",		GL_ARB_vertex_program_functions },
    { "GL_APPLE_vertex_array_object",	GL_APPLE_vertex_array_object_functions },
    { "GL_ATI_fragment_shader",		GL_ATI_fragment_shader_functions },
    { "GL_EXT_depth_bounds_test",	GL_EXT_depth_bounds_test_functions },
    { "GL_EXT_framebuffer_object",	GL_EXT_framebuffer_object_functions },
    { "GL_EXT_framebuffer_blit",	GL_EXT_framebuffer_blit_functions },
    { "GL_EXT_gpu_program_parameters",	GL_EXT_gpu_program_parameters_functions },
    { "GL_EXT_paletted_texture",	GL_EXT_paletted_texture_functions },
    { "GL_IBM_multimode_draw_arrays",	GL_IBM_multimode_draw_arrays_functions },
    { "GL_MESA_resize_buffers",		GL_MESA_resize_buffers_functions },
    { "GL_NV_vertex_program",		GL_NV_vertex_program_functions },
    { "GL_NV_fragment_program",		GL_NV_fragment_program_functions },
    { NULL,				NULL }
};


/**
 * Screen and config-related functions
 */

static void
setupLoaderExtensions(__DRIscreen *psp,
		      const __DRIextension **extensions)
{
    int i;

    for (i = 0; extensions[i]; i++) {
	if (strcmp(extensions[i]->name, __DRI_SWRAST_LOADER) == 0)
	    psp->swrast_loader = (__DRIswrastLoaderExtension *) extensions[i];
    }
}

static __DRIconfig **
swrastFillInModes(__DRIscreen *psp,
		  unsigned pixel_bits, unsigned depth_bits,
		  unsigned stencil_bits, GLboolean have_back_buffer)
{
    __DRIconfig **configs;
    unsigned depth_buffer_factor;
    unsigned back_buffer_factor;
    GLenum fb_format;
    GLenum fb_type;

    /* GLX_SWAP_COPY_OML is only supported because the Intel driver doesn't
     * support pageflipping at all.
     */
    static const GLenum back_buffer_modes[] = {
	GLX_NONE, GLX_SWAP_UNDEFINED_OML
    };

    u_int8_t depth_bits_array[4];
    u_int8_t stencil_bits_array[4];

    depth_bits_array[0] = 0;
    depth_bits_array[1] = 0;
    depth_bits_array[2] = depth_bits;
    depth_bits_array[3] = depth_bits;

    /* Just like with the accumulation buffer, always provide some modes
     * with a stencil buffer.
     */
    stencil_bits_array[0] = 0;
    stencil_bits_array[1] = (stencil_bits == 0) ? 8 : stencil_bits;
    stencil_bits_array[2] = 0;
    stencil_bits_array[3] = (stencil_bits == 0) ? 8 : stencil_bits;

    depth_buffer_factor = 4;
    back_buffer_factor = 2;

    if (pixel_bits == 8) {
	fb_format = GL_RGB;
	fb_type = GL_UNSIGNED_BYTE_2_3_3_REV;
    }
    else if (pixel_bits == 16) {
	fb_format = GL_RGB;
	fb_type = GL_UNSIGNED_SHORT_5_6_5;
    }
    else {
	fb_format = GL_BGRA;
	fb_type = GL_UNSIGNED_INT_8_8_8_8_REV;
    }

    configs = driCreateConfigs(fb_format, fb_type,
			       depth_bits_array, stencil_bits_array,
			       depth_buffer_factor, back_buffer_modes,
			       back_buffer_factor);
    if (configs == NULL) {
	fprintf(stderr, "[%s:%u] Error creating FBConfig!\n", __func__,
		__LINE__);
	return NULL;
    }

    return configs;
}

static __DRIscreen *
driCreateNewScreen(int scrn, const __DRIextension **extensions,
		   const __DRIconfig ***driver_configs, void *data)
{
    static const __DRIextension *emptyExtensionList[] = { NULL };
    __DRIscreen *psp;
    __DRIconfig **configs8, **configs16, **configs32;

    (void) data;

    TRACE;

    psp = _mesa_calloc(sizeof(*psp));
    if (!psp)
	return NULL;

    setupLoaderExtensions(psp, extensions);

    psp->num = scrn;
    psp->extensions = emptyExtensionList;

    configs8  = swrastFillInModes(psp,  8,  8, 0, 1);
    configs16 = swrastFillInModes(psp, 16, 16, 0, 1);
    configs32 = swrastFillInModes(psp, 32, 24, 8, 1);

    configs16 = (__DRIconfig **)driConcatConfigs(configs8, configs16);

    *driver_configs = driConcatConfigs(configs16, configs32);

    driInitExtensions( NULL, card_extensions, GL_FALSE );

    return psp;
}

static void driDestroyScreen(__DRIscreen *psp)
{
    TRACE;

    if (psp) {
	_mesa_free(psp);
    }
}

static const __DRIextension **driGetExtensions(__DRIscreen *psp)
{
    TRACE;

    return psp->extensions;
}


/**
 * Framebuffer and renderbuffer-related functions.
 */

static GLuint
choose_pixel_format(const GLvisual *v)
{
    if (v->rgbMode) {
	int bpp = v->rgbBits;

	if (bpp == 32
	    && v->redMask   == 0xff0000
	    && v->greenMask == 0x00ff00
	    && v->blueMask  == 0x0000ff)
	    return PF_A8R8G8B8;
	else if (bpp == 16
	    && v->redMask   == 0xf800
	    && v->greenMask == 0x07e0
	    && v->blueMask  == 0x001f)
	    return PF_R5G6B5;
	else if (bpp == 8
	    && v->redMask   == 0x07
	    && v->greenMask == 0x38
	    && v->blueMask  == 0xc0)
	    return PF_R3G3B2;
    }
    else {
	if (v->indexBits == 8)
	    return PF_CI8;
    }

    _mesa_problem( NULL, "unexpected format in %s", __FUNCTION__ );
    return 0;
}

static void
swrast_delete_renderbuffer(struct gl_renderbuffer *rb)
{
    TRACE;

    _mesa_free(rb->Data);
    _mesa_free(rb);
}

static GLboolean
swrast_alloc_front_storage(GLcontext *ctx, struct gl_renderbuffer *rb,
			   GLenum internalFormat, GLuint width, GLuint height)
{
    struct swrast_renderbuffer *xrb = swrast_renderbuffer(rb);
    int bpp;
    unsigned mask = PITCH_ALIGN_BITS - 1;

    TRACE;

    rb->Data = NULL;
    rb->Width = width;
    rb->Height = height;

    switch (internalFormat) {
    case GL_RGB:
	bpp = rb->RedBits + rb->GreenBits + rb->BlueBits;
	break;
    case GL_RGBA:
	bpp = rb->RedBits + rb->GreenBits + rb->BlueBits + rb->AlphaBits;
	break;
    case GL_COLOR_INDEX8_EXT:
	bpp = rb->IndexBits;
	break;
    default:
	_mesa_problem( NULL, "unexpected format in %s", __FUNCTION__ );
	return GL_FALSE;
    }

    /* always pad to PITCH_ALIGN_BITS */
    xrb->pitch = ((width * bpp + mask) & ~mask) / 8;

    return GL_TRUE;
}

static GLboolean
swrast_alloc_back_storage(GLcontext *ctx, struct gl_renderbuffer *rb,
			  GLenum internalFormat, GLuint width, GLuint height)
{
    struct swrast_renderbuffer *xrb = swrast_renderbuffer(rb);

    TRACE;

    _mesa_free(rb->Data);

    swrast_alloc_front_storage(ctx, rb, internalFormat, width, height);

    rb->Data = _mesa_malloc(height * xrb->pitch);

    return GL_TRUE;
}

static struct swrast_renderbuffer *
swrast_new_renderbuffer(const GLvisual *visual, GLboolean front)
{
    struct swrast_renderbuffer *xrb = _mesa_calloc(sizeof *xrb);
    GLuint pixel_format;

    TRACE;

    if (!xrb)
	return NULL;

    _mesa_init_renderbuffer(&xrb->Base, 0);

    pixel_format = choose_pixel_format(visual);

    xrb->Base.Delete = swrast_delete_renderbuffer;
    if (front) {
	xrb->Base.AllocStorage = swrast_alloc_front_storage;
	swrast_set_span_funcs_front(xrb, pixel_format);
    }
    else {
	xrb->Base.AllocStorage = swrast_alloc_back_storage;
	swrast_set_span_funcs_back(xrb, pixel_format);
    }

    switch (pixel_format) {
    case PF_A8R8G8B8:
	xrb->Base.InternalFormat = GL_RGBA;
	xrb->Base._BaseFormat = GL_RGBA;