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ICG2011 Hwk2 - How to do?. It’ll introduce. How to do Hwk2 step by step . No code. About Hwk2…. Texture Retargeting. Load an image as texture, and retargeting it over any surface/object file . Read hwk2 for more details. Step1: Texture. Read the example code , …
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It’ll introduce • How to do Hwk2 step by step. • No code.
About Hwk2… • Texture Retargeting. • Load an image as texture, and retargeting it over any surface/object file. • Read hwk2 for more details.
Step1: Texture • Read the example code, … • Draw a Quad with texture.
Step2: GL_SELECT • Set name/PickMatrix to the quad, thus when user click on the polygon, program will return a signal. • You must use glSelect on the quad, or get no grade! When click!!
In pickSquares… (void) glRenderMode (GL_SELECT); glInitNames(); glPushName(0); glMatrixMode (GL_PROJECTION); glPushMatrix (); glLoadIdentity (); gluPickMatrix ((GLdouble) x, (GLdouble) (viewport[3] - y), 20.0, 20.0, viewport); gluOrtho2D (0.0, 3.0, 0.0, 3.0); drawSquaresSelect(); glMatrixMode (GL_PROJECTION); glPopMatrix (); glFlush (); hits = glRenderMode (GL_RENDER); Define view volume Draw selection Buffer Draw your quad in this function again, and before drawing, use LoadName() and PushName() to assign a distinct name to the quad.
Step3: Define texture coordinate • Calculate the texture coordinate of point user clicked. (1,0) (1,1) This point’s coordinate is near (0.5,0.25) (0,0) (0,1)
Step4: Retarget on other polygon (70%) • Click 3~4 times, and store the coordinate. • Draw a new polygon(triangle or quad, up to click times), and give each vertices the stored coordinate.
Step5: GL_SELECT on mesh • Generate a mesh, and set each vertices a name. • Your program has to “pick” each vertices user clicked. When click, program knows which vertex is clicked.
Step6: Select vertices in region • After click 3 vertices (triangle is simpler), program give each vertices in the triangle region a distinct texture coordinate. • Program have to “scan” which vertices is in the region. • To each points(in screen) in the region, try pickMatrix() to select.
Step7: Give each vertex a coordinate • Use interpolation to give each vertex a coordinate. • Interpolation from 3 boundary vertex (user select). (1,0) (1,0) 0.7 0.3 (0.7,0.3) 0.3 (0,0.7) =>(0.35,0.5) (0,1) 0.7 (0.35,0.5) (0,0) (0,1) (0,0) Texture Mesh
Step8: Display (85%) • Only display when polygon’s 3 vertices have assigned texture coordinate.
Step9: Obj loader(100%+?) • Use mesh.h/mesh.cpp loading obj files. • You may use vertices’ sequence as name. • Same as step 5~9. • You may generate a simple obj file for debugging, like quadric mesh (as step 5). – lower grade, maybe 95? • For outlier, use face_list in mesh loader to select all outlier vertices.
