1GLTEXIMAGE2D(3G) OpenGL Manual GLTEXIMAGE2D(3G)
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6 glTexImage2D - specify a two-dimensional texture image
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9 void glTexImage2D(GLenum target, GLint level, GLint internalFormat,
10 GLsizei width, GLsizei height, GLint border,
11 GLenum format, GLenum type, const GLvoid * data);
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14 target
15 Specifies the target texture. Must be GL_TEXTURE_2D,
16 GL_PROXY_TEXTURE_2D, GL_TEXTURE_1D_ARRAY,
17 GL_PROXY_TEXTURE_1D_ARRAY, GL_TEXTURE_RECTANGLE,
18 GL_PROXY_TEXTURE_RECTANGLE, GL_TEXTURE_CUBE_MAP_POSITIVE_X,
19 GL_TEXTURE_CUBE_MAP_NEGATIVE_X, GL_TEXTURE_CUBE_MAP_POSITIVE_Y,
20 GL_TEXTURE_CUBE_MAP_NEGATIVE_Y, GL_TEXTURE_CUBE_MAP_POSITIVE_Z,
21 GL_TEXTURE_CUBE_MAP_NEGATIVE_Z, or GL_PROXY_TEXTURE_CUBE_MAP.
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23 level
24 Specifies the level-of-detail number. Level 0 is the base image
25 level. Level n is the nth mipmap reduction image. If target is
26 GL_TEXTURE_RECTANGLE or GL_PROXY_TEXTURE_RECTANGLE, level must be
27 0.
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29 internalFormat
30 Specifies the number of color components in the texture. Must be
31 one of base internal formats given in Table 1, one of the sized
32 internal formats given in Table 2, or one of the compressed
33 internal formats given in Table 3, below.
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35 width
36 Specifies the width of the texture image. All implementations
37 support texture images that are at least 1024 texels wide.
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39 height
40 Specifies the height of the texture image, or the number of layers
41 in a texture array, in the case of the GL_TEXTURE_1D_ARRAY and
42 GL_PROXY_TEXTURE_1D_ARRAY targets. All implementations support 2D
43 texture images that are at least 1024 texels high, and texture
44 arrays that are at least 256 layers deep.
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46 border
47 This value must be 0.
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49 format
50 Specifies the format of the pixel data. The following symbolic
51 values are accepted: GL_RED, GL_RG, GL_RGB, GL_BGR, GL_RGBA, and
52 GL_BGRA.
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54 type
55 Specifies the data type of the pixel data. The following symbolic
56 values are accepted: GL_UNSIGNED_BYTE, GL_BYTE, GL_UNSIGNED_SHORT,
57 GL_SHORT, GL_UNSIGNED_INT, GL_INT, GL_FLOAT,
58 GL_UNSIGNED_BYTE_3_3_2, GL_UNSIGNED_BYTE_2_3_3_REV,
59 GL_UNSIGNED_SHORT_5_6_5, GL_UNSIGNED_SHORT_5_6_5_REV,
60 GL_UNSIGNED_SHORT_4_4_4_4, GL_UNSIGNED_SHORT_4_4_4_4_REV,
61 GL_UNSIGNED_SHORT_5_5_5_1, GL_UNSIGNED_SHORT_1_5_5_5_REV,
62 GL_UNSIGNED_INT_8_8_8_8, GL_UNSIGNED_INT_8_8_8_8_REV,
63 GL_UNSIGNED_INT_10_10_10_2, and GL_UNSIGNED_INT_2_10_10_10_REV.
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65 data
66 Specifies a pointer to the image data in memory.
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69 Texturing allows elements of an image array to be read by shaders.
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71 To define texture images, call glTexImage2D. The arguments describe the
72 parameters of the texture image, such as height, width, width of the
73 border, level-of-detail number (see glTexParameter()), and number of
74 color components provided. The last three arguments describe how the
75 image is represented in memory.
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77 If target is GL_PROXY_TEXTURE_2D, GL_PROXY_TEXTURE_1D_ARRAY,
78 GL_PROXY_TEXTURE_CUBE_MAP, or GL_PROXY_TEXTURE_RECTANGLE, no data is
79 read from data, but all of the texture image state is recalculated,
80 checked for consistency, and checked against the implementation's
81 capabilities. If the implementation cannot handle a texture of the
82 requested texture size, it sets all of the image state to 0, but does
83 not generate an error (see glGetError()). To query for an entire mipmap
84 array, use an image array level greater than or equal to 1.
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86 If target is GL_TEXTURE_2D, GL_TEXTURE_RECTANGLE or one of the
87 GL_TEXTURE_CUBE_MAP targets, data is read from data as a sequence of
88 signed or unsigned bytes, shorts, or longs, or single-precision
89 floating-point values, depending on type. These values are grouped into
90 sets of one, two, three, or four values, depending on format, to form
91 elements. Each data byte is treated as eight 1-bit elements, with bit
92 ordering determined by GL_UNPACK_LSB_FIRST (see glPixelStore()).
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94 If target is GL_TEXTURE_1D_ARRAY, data is interpreted as an array of
95 one-dimensional images.
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97 If a non-zero named buffer object is bound to the
98 GL_PIXEL_UNPACK_BUFFER target (see glBindBuffer()) while a texture
99 image is specified, data is treated as a byte offset into the buffer
100 object's data store.
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102 The first element corresponds to the lower left corner of the texture
103 image. Subsequent elements progress left-to-right through the remaining
104 texels in the lowest row of the texture image, and then in successively
105 higher rows of the texture image. The final element corresponds to the
106 upper right corner of the texture image.
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108 format determines the composition of each element in data. It can
109 assume one of these symbolic values:
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111 GL_RED
112 Each element is a single red component. The GL converts it to
113 floating point and assembles it into an RGBA element by attaching 0
114 for green and blue, and 1 for alpha. Each component is then
115 multiplied by the signed scale factor GL_c_SCALE, added to the
116 signed bias GL_c_BIAS, and clamped to the range [0,1].
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118 GL_RG
119 Each element is a red/green double. The GL converts it to floating
120 point and assembles it into an RGBA element by attaching 0 for
121 blue, and 1 for alpha. Each component is then multiplied by the
122 signed scale factor GL_c_SCALE, added to the signed bias GL_c_BIAS,
123 and clamped to the range [0,1].
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125 GL_RGB
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127 GL_BGR
128 Each element is an RGB triple. The GL converts it to floating point
129 and assembles it into an RGBA element by attaching 1 for alpha.
130 Each component is then multiplied by the signed scale factor
131 GL_c_SCALE, added to the signed bias GL_c_BIAS, and clamped to the
132 range [0,1].
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134 GL_RGBA
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136 GL_BGRA
137 Each element contains all four components. Each component is
138 multiplied by the signed scale factor GL_c_SCALE, added to the
139 signed bias GL_c_BIAS, and clamped to the range [0,1].
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141 GL_DEPTH_COMPONENT
142 Each element is a single depth value. The GL converts it to
143 floating point, multiplies by the signed scale factor
144 GL_DEPTH_SCALE, adds the signed bias GL_DEPTH_BIAS, and clamps to
145 the range [0,1].
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147 GL_DEPTH_STENCIL
148 Each element is a pair of depth and stencil values. The depth
149 component of the pair is interpreted as in GL_DEPTH_COMPONENT. The
150 stencil component is interpreted based on specified the depth +
151 stencil internal format.
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153 If an application wants to store the texture at a certain resolution or
154 in a certain format, it can request the resolution and format with
155 internalFormat. The GL will choose an internal representation that
156 closely approximates that requested by internalFormat, but it may not
157 match exactly. (The representations specified by GL_RED, GL_RG, GL_RGB,
158 and GL_RGBA must match exactly.)
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160 internalFormat may be one of the base internal formats shown in Table
161 1, below
162
163 <xi:include></xi:include>
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165 internalFormat may also be one of the sized internal formats shown in
166 Table 2, below
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168 <xi:include></xi:include>
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170 Finally, internalFormat may also be one of the generic or compressed
171 compressed texture formats shown in Table 3 below
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173 <xi:include></xi:include>
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175 If the internalFormat parameter is one of the generic compressed
176 formats, GL_COMPRESSED_RED, GL_COMPRESSED_RG, GL_COMPRESSED_RGB, or
177 GL_COMPRESSED_RGBA, the GL will replace the internal format with the
178 symbolic constant for a specific internal format and compress the
179 texture before storage. If no corresponding internal format is
180 available, or the GL can not compress that image for any reason, the
181 internal format is instead replaced with a corresponding base internal
182 format.
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184 If the internalFormat parameter is GL_SRGB, GL_SRGB8, GL_SRGB_ALPHA, or
185 GL_SRGB8_ALPHA8, the texture is treated as if the red, green, or blue
186 components are encoded in the sRGB color space. Any alpha component is
187 left unchanged. The conversion from the sRGB encoded component c s to a
188 linear component c l is:
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190 c l = { c s 12.92 if c s ≤ 0.04045 ( c s + 0.055 1.055 ) 2.4 if c s >
191 0.04045
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193 Assume c s is the sRGB component in the range [0,1].
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195 Use the GL_PROXY_TEXTURE_2D, GL_PROXY_TEXTURE_1D_ARRAY,
196 GL_PROXY_TEXTURE_RECTANGLE, or GL_PROXY_TEXTURE_CUBE_MAP target to try
197 out a resolution and format. The implementation will update and
198 recompute its best match for the requested storage resolution and
199 format. To then query this state, call glGetTexLevelParameter(). If the
200 texture cannot be accommodated, texture state is set to 0.
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202 A one-component texture image uses only the red component of the RGBA
203 color extracted from data. A two-component image uses the R and G
204 values. A three-component image uses the R, G, and B values. A
205 four-component image uses all of the RGBA components.
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207 Image-based shadowing can be enabled by comparing texture r coordinates
208 to depth texture values to generate a boolean result. See
209 glTexParameter() for details on texture comparison.
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212 The glPixelStore() mode affects texture images.
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214 data may be a null pointer. In this case, texture memory is allocated
215 to accommodate a texture of width width and height height. You can then
216 download subtextures to initialize this texture memory. The image is
217 undefined if the user tries to apply an uninitialized portion of the
218 texture image to a primitive.
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220 glTexImage2D specifies the two-dimensional texture for the current
221 texture unit, specified with glActiveTexture().
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224 GL_INVALID_ENUM is generated if target is not GL_TEXTURE_2D,
225 GL_TEXTURE_1D_ARRAY, GL_TEXTURE_RECTANGLE, GL_PROXY_TEXTURE_2D,
226 GL_PROXY_TEXTURE_1D_ARRAY, GL_PROXY_TEXTURE_RECTANGLE,
227 GL_PROXY_TEXTURE_CUBE_MAP, GL_TEXTURE_CUBE_MAP_POSITIVE_X,
228 GL_TEXTURE_CUBE_MAP_NEGATIVE_X, GL_TEXTURE_CUBE_MAP_POSITIVE_Y,
229 GL_TEXTURE_CUBE_MAP_NEGATIVE_Y, GL_TEXTURE_CUBE_MAP_POSITIVE_Z, or
230 GL_TEXTURE_CUBE_MAP_NEGATIVE_Z.
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232 GL_INVALID_ENUM is generated if target is one of the six cube map 2D
233 image targets and the width and height parameters are not equal.
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235 GL_INVALID_ENUM is generated if type is not a type constant.
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237 GL_INVALID_VALUE is generated if width is less than 0 or greater than
238 GL_MAX_TEXTURE_SIZE.
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240 GL_INVALID_VALUE is generated if target is not GL_TEXTURE_1D_ARRAY or
241 GL_PROXY_TEXTURE_1D_ARRAY and height is less than 0 or greater than
242 GL_MAX_TEXTURE_SIZE.
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244 GL_INVALID_VALUE is generated if target is GL_TEXTURE_1D_ARRAY or
245 GL_PROXY_TEXTURE_1D_ARRAY and height is less than 0 or greater than
246 GL_MAX_ARRAY_TEXTURE_LAYERS.
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248 GL_INVALID_VALUE is generated if level is less than 0.
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250 GL_INVALID_VALUE may be generated if level is greater than log 2 max,
251 where max is the returned value of GL_MAX_TEXTURE_SIZE.
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253 GL_INVALID_VALUE is generated if internalFormat is not one of the
254 accepted resolution and format symbolic constants.
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256 GL_INVALID_VALUE is generated if width or height is less than 0 or
257 greater than GL_MAX_TEXTURE_SIZE.
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259 GL_INVALID_VALUE is generated if non-power-of-two textures are not
260 supported and the width or height cannot be represented as 2 k + 2
261 border for some integer value of k.
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263 GL_INVALID_VALUE is generated if border is not 0.
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265 GL_INVALID_OPERATION is generated if type is one of
266 GL_UNSIGNED_BYTE_3_3_2, GL_UNSIGNED_BYTE_2_3_3_REV,
267 GL_UNSIGNED_SHORT_5_6_5, GL_UNSIGNED_SHORT_5_6_5_REV, or
268 GL_UNSIGNED_INT_10F_11F_11F_REV, and format is not GL_RGB.
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270 GL_INVALID_OPERATION is generated if type is one of
271 GL_UNSIGNED_SHORT_4_4_4_4, GL_UNSIGNED_SHORT_4_4_4_4_REV,
272 GL_UNSIGNED_SHORT_5_5_5_1, GL_UNSIGNED_SHORT_1_5_5_5_REV,
273 GL_UNSIGNED_INT_8_8_8_8, GL_UNSIGNED_INT_8_8_8_8_REV,
274 GL_UNSIGNED_INT_10_10_10_2, GL_UNSIGNED_INT_2_10_10_10_REV, or
275 GL_UNSIGNED_INT_5_9_9_9_REV, and format is neither GL_RGBA nor GL_BGRA.
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277 GL_INVALID_OPERATION is generated if target is not GL_TEXTURE_2D,
278 GL_PROXY_TEXTURE_2D, GL_TEXTURE_RECTANGLE, or
279 GL_PROXY_TEXTURE_RECTANGLE, and internalFormat is GL_DEPTH_COMPONENT,
280 GL_DEPTH_COMPONENT16, GL_DEPTH_COMPONENT24, or GL_DEPTH_COMPONENT32F.
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282 GL_INVALID_OPERATION is generated if format is GL_DEPTH_COMPONENT and
283 internalFormat is not GL_DEPTH_COMPONENT, GL_DEPTH_COMPONENT16,
284 GL_DEPTH_COMPONENT24, or GL_DEPTH_COMPONENT32F.
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286 GL_INVALID_OPERATION is generated if internalFormat is
287 GL_DEPTH_COMPONENT, GL_DEPTH_COMPONENT16, GL_DEPTH_COMPONENT24, or
288 GL_DEPTH_COMPONENT32F, and format is not GL_DEPTH_COMPONENT.
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290 GL_INVALID_OPERATION is generated if a non-zero buffer object name is
291 bound to the GL_PIXEL_UNPACK_BUFFER target and the buffer object's data
292 store is currently mapped.
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294 GL_INVALID_OPERATION is generated if a non-zero buffer object name is
295 bound to the GL_PIXEL_UNPACK_BUFFER target and the data would be
296 unpacked from the buffer object such that the memory reads required
297 would exceed the data store size.
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299 GL_INVALID_OPERATION is generated if a non-zero buffer object name is
300 bound to the GL_PIXEL_UNPACK_BUFFER target and data is not evenly
301 divisible into the number of bytes needed to store in memory a datum
302 indicated by type.
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304 GL_INVALID_VALUE is generated if target is GL_TEXTURE_RECTANGLE or
305 GL_PROXY_TEXTURE_RECTANGLE and level is not 0.
306
308 glGetTexImage()
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310 glGet() with argument GL_PIXEL_UNPACK_BUFFER_BINDING
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313 glActiveTexture(), glCopyTexImage1D(), glCopyTexImage2D(),
314 glCopyTexSubImage1D(), glCopyTexSubImage2D(), glCopyTexSubImage3D(),
315 glPixelStore(), glTexImage1D(), glTexImage3D(), glTexSubImage1D(),
316 glTexSubImage2D(), glTexSubImage3D(), glTexParameter()
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319 Copyright © 1991-2006 Silicon Graphics, Inc. Copyright © 2011 Khronos
320 Group. This document is licensed under the SGI Free Software B License.
321 For details, see http://oss.sgi.com/projects/FreeB/.
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